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How should you search?

This site presents a variety of methods and tools to help your literature search.

Start by considering which types of materials suit your information needs. All the tools you need to find books, articles, legislation, pictures etc. are available in the list of databases. The overview of the central tools of your field of study can be found in the library’s subject guides. If you have not worked with databases previously, you can start by learning more about it here.

Before you begin your actual search, it might be a good idea to set some time aside to get an overview of the nature of your assignment, its scale, and its deadline. This will help you to create a timetable for your literature search.

Create a timeframe around your literature search:

  • Study the demands regarding the type and scale of literature needed for the paper
  • Make arrangements for any help you might need for searches
  • Set time aside to do an info search and study abstracts
  • Set time aside to do an info search a couple of times if you are dealing with a lengthy paper
  • Set a date when you need to talk about your literature search with your supervisor, and when you need to present a search strategy/a bibliography to your supervisor
  • Set a deadline for collecting data and studying the literature – as soon as possible in relation to the final deadline.

This advice is taken from "The good Paper" by Lotte Rienecker and Peter Stray Jørgensen.


Different types of literature search

  • Start with works of reference to get an overview. You can find a broad selection of digital works of reference on the library’s list of databases. The central works of reference for any field of study are shown in the library’s subject guides 
  • Use books to get a broad background. To begin with, search for books on Bibliotek.dk and AU Library
  • Use articles to get a new and more focused understanding. Danish articles can be found on Bibliotek.dk. You can find journals from your own field of study in the library’s subject guides
  • Start with an inspiration search (search methods “Quick’n’Dirty” and “Citation Pearl Growing”) in the process from choosing your topic to picking your research question
  • Use a systematic search (search methods “search strategy” and “search using keywords”) when you have an idea of your literature needs.

Method: Quick'n'dirty

If your topic is relatively unknown to you, or if you are simply in doubt about whether anyone has written anything about it before, you can search first and then consider your options afterwards.

A Quick’n’Dirty search is a good way to get an overview of what type of literature that exists and which terms and keywords have been used to describe the topic:

  • Use AU Library, Bibliotek.dk, or a database that might contain literature on your topic
  • Search using words and terms that you already know
  • Use these search results to learn more about the technical terms and the “right” search words
  • Continue searching using the new terms and search words.


AU Library allows you to search through roughly 200 million digital articles in addition to your regular search of the library’s books etc.

You can find the articles under the heading “Full text about...” amongst the search results.


It’s an advantage to start by using works of references and guides. They can be vital, giving you a clear idea of the terminology and important publications of the field.

Method: Citation Pearl Growing

Find both old and new literature about your topic by searching for something familiar.

Searching for literature or information is all about filling the “gap” between what you already know about a topic, and what you need to know. You can use the literature with which you are already familiar as a point of departure for finding more literature on the same topic:

  • You can use the bibliographies of the best books and articles that you have found already to find new literature
  • Then you can use the bibliographies of these new books/articles to find more literature about the subject.  

The references you find in the bibliographies often belong to the same tradition, paradigm or school of thought. So you will need one or more additional search methods if you want to find literature that can discuss or oppose the literature you have found already.

Here is an example of how to use the chain search.

Old or new literature?

When you use a chain search strategy by using bibliographies, you will only find books and articles that predate the book or article in which the bibliography is printed.

When you search for your book or article in a database and get an overview of books and articles with the same topic or keywords, you may find newly published materials on your subject. You can also use citation indexes to find matches between citations or to find the bibliographies or references of the individual texts. Read more about this below under "Tips and Tricks for your literature search".

Search strategy

Decide on a strategy for your search to give you insight into specialist terminology or what you need to know.

Use your research question as a point of departure to isolate the terms that occur in the literature you have found.

Do a broad literature search first – for example online – to get a quick overview of the topic you want to examine in connection with your research question.


For each search word:

  • Consider which synonyms you should include to make your search as complete as possible
  • Find suggestions for broader and narrower terms for your search words. This will give you the chance to make progress even though you find no research results – or too many results – when you search.


Think about how to limit your searches

  • Which languages am I looking for?
  • Is there a geographical scope for my searches?
  • Am I interested in a specific, limited period of time?
  • How new should the literature I want to read be?
  • What type of information do I want: Outlines? Only the most recent? Attitudes and comments, or reviews? Or literally anything about the subject?

Here is an example of how to use the search triangle in connection with your search strategy:

Precision and versatility in your searches

When your searches do not yield the expected results, the problem might be that the relationship between precision and retrieval does not match your needs. Here is an explanation of what precision and retrieval mean, and how to achieve the right balance between them.

Depending on the type of paper involved, it might be an advantage to choose a search strategy that gives priority to a high degree of precision or a large number of retrievals.

  • The less time you spend on searching, the more you will depend on the precision of your searches   
  • The longer you spend on searching, the greater the depth of your searches (usually). 

The table below shows you which tactics you can use to improve your search results – whether you want a small number of precise results, or a large number of broad results.




A search with great precision is a search that:

  • Retrieves a few items, most of which will be exactly what you need
  • Retrieves information from one or two authoritative sources
  • Gives you precisely the information you need
  • Can be used for factual searches.    


A search with many retrievals is a search that:

  • Retrieves a lot of items, some of which will be exactly what you need while others will be useful to some extent
  • Often needs many keywords, synonyms, searches for authors etc.
  • Is often very time-consuming and should involve various databases and sources
  • Can be used to examine a subject field or a problem area.    


Logbooks can help you to maintain and develop your awareness of the process involved in your information searches. Your logbook can be used to record:  

  • Where you search
  • Which search words you employ
  • The result of your search.

You will save time and reduce any frustration if you keep a logbook from day one. It will help you to remember where (and how) you have searched.

It will also help you to follow up on your literature searches later on in your writing process.

Method: Search with keywords

In many databases, precise keywords have been assigned to the individual posts. You can use them to increase the focus of your search.

Instead of using your own words when searching – check out Quick’n’Dirty – it may be a good idea to discover the terms that the database uses to characterise certain books and articles in the database.

Almost all the databases that you can find on AU Library’s list of databases have a list of keywords. You should look for:

  • Subject terms
  • Index (keyword index or descriptor index)
  • Thesaurus.

You can now use the list to search for suitable words for your search. You can use this to draw up a list of the terms and synonyms that you will use in a search. You can also conduct a search of the words and terms that you find in the list of keywords and combine the different searches afterwards.

Here is an example of how to use a database’s list of keywords.

Searching with confirmed keywords

At a later stage of your search process you might need searches with greater precision. If you want to increase your precision, you can use confirmed keywords.

The operators of the databases for international, academic databases evaluate the literature that is indexed and assign certain keywords, either from a thesaurus or from a list of keywords – this is why they are called “confirmed keywords”.

The allocation of confirmed keywords ensures that articles about the same topic are indexed in the same way. These registers or lists of keywords can help you to broaden or limit your searches. The confirmed keywords are typically different from database to database. Read more about ‘thesaurus’ under “Tips and tricks for the literature search” below.

Tips and tricks for the literature search

Achieve better search results. 

You will often need to adjust your search strategy as you go along. Either because you become more aware of what has been written about the topic, or because you do not immediately find what you need.

You want to search for...


…multiple endings 


Truncation gives you the option of combining a search with all varieties of word endings. You can also search for different spellings of the same word. You can use a special truncation symbol in almost all databases.

“Discourse*” searches for the root of the word and all types of derivations – e.g.:

  • Discourse
  • Discourses
  • Discoursing
  • Discourse theory.    

…different spellings


Masking enables you to allow for different spellings when searching. In some databases you can replace one, two or three symbols using a masking symbol.

Write “Pe?ersen” in order to find results with both “Petersen” and “Pedersen”. 

Another option is “col?r” to take the different spellings of “colour” and “color” into account.

Truncation and masking symbols are almost always either “*” or “?”.    

…relations between the topics    


A thesaurus is a list of keywords which has been expanded to include the relationship between individual words. When you find a term in the list, you also get:

  • A brief description of the term
  • The concepts which it replaces
  • Closely related terms
  • Broader and narrower terms.


A thesaurus defines the relationship of keywords to each other – typically in:

  • BT ‘Broader terms’
  • NT ‘Narrower terms’
  • RT ‘Related terms’.    

...References or matches between the texts.

Citation index

Citation indexes are databases that have been created especially for chain searches.

You make a direct search for individual articles, bibliographies or references. This helps you to find older literature by using a specific article and using its bibliography, and newer literature by using the information about which later articles cite the specific article.

You can also use citation indexes to find documents which have matching citations and which may therefore be topically related.        

...More than one word

Boolean operators

You can state the relationship between your search words by using the so-called Boolean operators. These operators are the three words: “and”, “or”, and “not”.

  • And – finds the results in which both words occur: Learning AND education
  • Or – finds the results in which only one of the words occurs: Learning OR education
  • Not – finds the results in which the first word occurs but not the second one: Learning NOT education.
Try googling “Boolean operators” for a presentation of how to use AND, OR and NOT.    

Achieving the results you want

Undertaking a search process can be a bit of a challenge, and your searches might not produce the results you want. When you search for information, you might not find what you are looking for. Here are some tips about how to improve your search if you get too many or too few results – or simply the wrong results. 

You get...


...too few results 

  • Check your search words for spelling or typing mistakes
  • Check whether you have used “and”, “or”, or “not” correctly
  • Truncate your search words
  • Find more synonyms for your search words
  • If you have delimited your search – for example in relation to time and geography – make these limits broader or simply omit them
  • Search using fewer search words
  • Search in other databases.    

…too many results    

  • Search for your selected narrow terms
  • Check whether you have used “and”, “or”, and “not” correctly
  • Use quotation marks around a sentence to search precisely for the combined content – e.g. “Quality in further education”.    

…the wrong results    

  • Decide whether you have truncated your search words so much that you might also be searching for words outside your field of interest
  • Check whether some of your search words might have a different meaning than the intended meaning 
  • Search in other databases.    

And check:

Leading authors and well-known publishers:

  • When you chain search and analyse bibliographies, you will find the leading authors on your topic
  • Search for authors in the bibliographical databases. They might have published literature that is newer than what you currently have found
  • Is it a university publishing company that has published a book, or is it a commercially run publishing company? A publisher’s name and affiliations may indicate quality. 

Works of reference:

  • If you have a lot of references from various bibliographies, trust the references provided by review articles in encyclopaedias and other reference works.    

Reference management on AU Library

If you need more information on reference management AU Library has made a page on the topic. Here you will find information on different standards for referencing and advice on how to handle a large amount of references in major assignments.

Courses in reference management

AU Library regularly offers courses regarding programmes that can be used for managing references. You can get access to these programmes as a student at Aarhus University. Read more and sign up at AU Library

The content of this page is written by Centre for Teaching Development and Digital Media, Arts, Aarhus Universitet in collaboration with Søren Elle, AU Library Arts, Jette Bohn, AU Library Arts, Anders Nyegaard Mikkelsen, former employee at AU Library Campus Emdrup and Jesper Boserup Thestrup, Royal Danish Library.