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PolyU Library

Conduct a Literature Review

A guide to walk you through the process of doing a literature review

Build an Effective Search Statement

Once you have collected a few keywords from your research topic, you can start searching for relevant studies. 

You can start with a basic search by typing in all the keywords in the search box and then run a search.

Basic Search
Enter a search term Search
Basic Search allows you to type in all keywords in one line. You can specify the field to search within, e.g. title, subject. However, this sometimes may not bring you satisfactory results.


By switching to Advanced Search, you are able to build a more structured search statement. This helps you find relevant results more efficiently. 

Advanced Search
  Enter a search term
Enter a search term
Enter a search term
  Add a New Line   Search

This is how Advanced Search looks like in OneSearch and many article databases. With the multiple lines structure, you can type in keywords representing different concepts in separate lines and specify the search field for each line.

You can also apply searching techniques, e.g. combine your search terms with Boolean operators (AND, OR, NOT) to make your search more precise.


Steps to Build a Search Statement

Build search statement - Steps

1. Identify keywords

From the preliminary search, you may have identified a few keywords and related terms from your research question. Pick 2-4 core keywords that represent different concepts. The keywords are usually nouns or noun phrasesWatch this video to learn a few more tips about picking keywords. 

Example topic: "The impact of COVID on the hotel industry in Hong Kong".

The keywords picked could be:  COVID, hotel industry, Hong Kong

2. Add keywords & combine them with "AND"

Go to OneSearch Advanced Search or an article database (e.g. Web of Science, Scopus) to build your search statement.

Use AND to combine the keywords so that the search results will include all these keywords.

To make your search more precise, you may:

  • Use quotation marks " " to enclose the phrase to search the terms as a phrase. This is known as a phrase search.
  • Specify search field, e.g. search within article title, subject, journal title. 

In our case: 

Advanced Search
  Any Fields COVID
AND Subject "hotel industry"
AND Any Fields Hong Kong
  Add a New Line   Search

If you run this search in OneSearch, you will notice there are very few results. This shows that the keywords you used may not be the keywords used in research papers. To make sure we do not miss out those studies, we need to expand our search by adding alternative keywords. 

3. Add synonyms/alternative terms & combine them with "OR"

Use OR to combine the alternative keywords (or synonyms) so that articles containing at least one of the keywords will be included in the results.

You may also:

  • Use truncations * to include variants of a word, e.g. travel* searches travel, travels, traveling, etc.
  • Use parentheses ( ) to enclose the phrase to specify the order (terms within parentheses will be executed first). 

In our case: 

Advanced Search
  Any Fields COVID OR coronavirus OR pandemic
AND Subject "hotel industry" OR hospitality OR tourism OR travel*
AND Title Hong Kong
  Add a New Line   Search

Check search results in OneSearch and see the difference. Note that we changed the search field of "Hong Kong" to "Title" so that only articles with "Hong Kong" in their title will be retrieved. This again makes our search more specific.

4. Refine search results by applying filters

The last step is to refine your search results using filters, e.g.

  • Peer-reviewed journals only
  • Publication year range
  • Subject category
  • and more

You can find similar filter options in OneSearch and many other article databases. 

Don't target for a perfect search statement on your first try! It is very common to refine your search statement until you retrieve a manageable number of relevant results. You may discover new keywords or even refine your research topic during the searching process.

Read More Search Tips to learn more about Boolean Operators, Truncations, and Phrase search.