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Search methods and techniques

Get a search strategy

Before you start searching for academic material, it is a good idea to work out a search strategy.  

Formulating a search strategy allows you to describe your approach to a given search task. For example, you could describe: 

  • Your topic 

  • The information you need 

  • Ways you will delimit (or narrow) your search  

It may be necessary to rethink your search strategy as you work on your research question or write your assignment. Searching for academic material is a circular process that develops as your research question takes shape and your knowledge of the topic improves. Below you will find some specific suggestions for how you can approach your search: 


Try different search techniques

Once you have formulated your search strategy, you can use a range of different techniques to help you find the information you need. 

Basic search 

A basic search is a good way to gain an initial overview of what is available and what concepts and words others have used about the topic. If you are relatively new to the subject, or if you are unsure whether anything has been written about it, you might consider starting this way.   

  1. Go to library.au.dk, bibliotek.dk or a database that is likely to contain relevant literature on your subject. 

You can also start by using reference books and textbooks to get an overview of the central terminology and works. 

  1. Use the words and concepts you already know to conduct a search. 

  1. Use the results of this search to learn more about the subject terminology and to find new keywords. 

  1. Conduct another search using these new keywords. 

Basic search - pros  

Basic search - cons 

A good way to get inspiration for your search 

Will not always give you the most relevant search results for your project 

Chain searches

A chain search allows you to use the references in the literature you have already found. Start by selecting a single article or book and searching for relevant titles in the reference list. By doing so, you will find literature that was published prior to the article or book you selected. 


How to conduct a chain search 

  1. Find a good article that is relevant to your subject and use this as a starting point. 
  2. Use the reference list at the end of the article to identify other relevant sources. 
  3. Repeat the process with the new relevant articles you have identified. 
Chain search - pros  Chain search - cons 
  • A quick way to find literature 
  • Can be used at the beginning of your search to help you explore the subject 
  • Is unlikely to help you find all the relevant literature  
  • The literature you find in the list of references will often belong to the same tradition, paradigm or school 
  • It is difficult to know when to stop  

Citation searches 

A citation search allows you to find relevant academic research by finding citations of the literature you already have. Start by selecting a single article and finding the articles that have cited this article. You can do this by finding the article in a citation index. By doing so, you will find the articles that have subsequently referred to the article you selected. 

How to conduct a citation search 

  1. Find a good article that is relevant to your subject and use this as a starting point. 
  2. Search for the article in a citation index, such as Web of Science, Scopus or Google Scholar 
  3. In the citation index, you will see a list of the articles that have referred to the article you selected. In other words, articles that were written after your original article and that have it in their reference list. 
  4. Once you are in the citation index, you can also find related articles, including articles with the same keywords. 

Citation search - pros 

Citation search - cons  

  • A quick way to find literature 
  • Can be used at the beginning of your search to help you explore the subject 
  • Be aware that Google Scholar also indexes non-academic publications 
  • The literature you find will often belong to the same tradition, paradigm or school – and can therefore end up being too one-sided and lacking counter argumentation 

Block searches

A block search is a way to structure your literature search. Divide your research question into topics and organise these into blocks, so that each block covers one topic. In each block, there will be search terms, controlled keywords and free text that cover the topic.

1. Choose your keywords 
  • Your keywords determine your search results. So it is worth spending time working on them. When choosing keywords, it is important you understand the terminology in the subject you are working on. This ensures that you search for the concepts that are used in the literature on the subject. 
  • Use your research question to help you identify your central topics. Make a list of keywords based on your research question.  
  • Find subject-specific keywords in reference works, in literature you already have on the topic (e.g. in an abstract, a blurb or a table of contents) or by asking a member of teaching staff on your course.   
  • If relevant, find “controlled” keywords in databases to supplement your free text search. Many databases assign controlled keywords to individual references, which are selected from a controlled vocabulary. Using controlled key words helps you to conduct a consistent search, because they enable you to find literature on the same topic regardless of the words that are used in the individual titles or abstracts, for example. Be aware that controlled keywords vary from database to database.  

Example: You are writing an assignment on the expansion of wolves across the Nordic region, so you need to find keywords about “wolves”, “expansion” and the “Nordic region”.

2. Synonyms, language and spelling 
  • Consider adding synonyms to your keywords to cover more of the subject – also in English, if this is not the language of your search. 
  • You can also use keywords from your selected database’s subject hierarchy or thesaurus instead of finding synonyms.  
  • Use truncation or masking if any of your keywords can be spelled in multiple ways – or search for a phrase if you would like to search for a precise combination of words.  
  • It may be a good idea to display the different topics in a diagram.  

Example: Once you have found keywords and synonyms for your search about the expansion of wolves across the Nordic region, you could display them in the following way:

3. Make your search string 

Example: (Wolf* OR “canis lupus”) AND (expansion OR spread OR distribution OR migration) AND (“Nordic region” OR “Nordic countries” OR Denmark OR Sweden OR Norway)

4. Delimit your search   
  • Delimit (narrow) your search by setting a time period, language or type of material  
5. Evaluate your search results 
6. Document your search   
  • Make a note of where you have searched, which search terms you have used, and which results you have got.   
  • If you keep a record of all your searches, you will save yourself time and frustration in the long term. 

Block search – pros  Block search – cons
  • Best technique for searching databases 
  • You can easily widen or narrow your search by removing or adding blocks 
  • Avoids bias 
  • Allows you to find gaps in the existing research 
  • Time-consuming process 

Use good search terms

The information you need will depend on the specific assignment you are writing. You may need literature or data, or you may need to verify information or find definitions.  

Regardless of the type of information you are looking for, it is important to use good search terms. Your search terms could be particular concepts, keywords or topic words. 

Use central terms from your research question

When you search for academic material, a relevant starting point would be to identify the central terms in your research question.   

Example You would like to explore the available options for people to monitor their blood pressure wirelessly at home. So you would like to know what the advantages and disadvantages are of patients taking their blood pressure themselves, as well as the technological opportunities to alleviate bias. In this case, it would be a good idea to search for terms such as “blood pressure monitoring at home” and “blood pressure monitoring equipment”. It may be necessary to conduct several searches before you get the information you require.  

By using the central terms in your research question, you will be able to conduct a preliminary search in engines such as Google Scholar or other relevant academic databases. This preliminary search can help you to get an overview of the topic and to identify more possible search terms. 

In this example, it may make sense to subsequently search for terms such as “educating patients”, “white coat syndrome”, “wireless monitoring” or “compliance”.  

Use synonyms

Consider whether there are any obvious synonyms for the search terms you identify. There are often many different words to describe a topic.  

  • Art nouveau, Jugendstil, Arts and Crafts movement  
  • Global warming, global change, greenhouse effect, climate change  
  • Breast cancer, breast neoplasms, breast tumours, mammary cancer  

To find synonyms, try looking in the articles, books and other materials you found in your preliminary search. Do these sources use other words? Look at the words in the title and the abstract, the author’s keywords, and controlled and uncontrolled keywords. 

Adjust your keywords

If you cannot find the literature you need, consider searching for terms that are related to your subject.  

Be creative and consider all the synonyms, partial synonyms, related concepts, synecdoches, opposites and abbreviations, and try using grammatical or semantic variations of your search terms.   

Examples of concepts: 
  • Umbrella concepts: For example, for ‘helicopters’ search for ‘air transportation’  
  • Subordinate concepts: For example, for ‘verbal communication’ search for ‘narratives’ 
  • Related concepts: For example, for ‘diets’ search for ‘food’  

You should also make sure you are looking in the right place. Are you looking in the right academic databases, for example? Find suggestions for other resources to help in your search for academic material here. 

Search tips

Here are some useful search tips to help get you started – or to help you if you are getting too many or too few results. 


Use an asterisk* in your search if you want your search to include multiple variations of the same word. For example, a search for wolf* will search for wolf, wolves and wolves’.  

Phrase search

Use quotation marks "... " if you want to search for a specific combination of words in a particular order. For example, a search for "Carnis Lupus" will only give you search results where these words are next to each other in this order.  

Boolean operators

Type AND, OR, NOT between your search terms to combine, expand, or narrow your search result. Remember to write AND, OR, NOT in capital letters. 

AND AND finds search results in which all the search terms appear. For example, a search for learning AND children will only include articles that include both learning and children 
OR OR finds search results in which just one of the words appears. For example, a search for learning OR education will include articles containing both or just one word. 
NOT NOT finds search results in which the first word appears but not the second word. For example, a search for jaguar NOT car will include articles in which jaguars appear but car does not appear. 

Widen or narrow your search

Too many results If you are getting too many results, you can narrow your search using the filtering options that most databases offer, For example, you can search for results within a certain time frame or in a certain language. It may also be worth checking that you have used the correct Boolean operators or searching again with more precise search terms, using a thesaurus to help you. 
Too few results If you are getting too few results, check that you have spelled everything correctly and that you have used the correct Boolean operators. You may also want to reconsider your search terms. For example, it could be worth finding synonyms or using broader terms. You can use a thesuarus to help you. You could also try searching in a different database. 

Example of a search: