Finding scientific information: Designing a search string

Designing a search string

With the help of a search string you will get the most versatile search possibilities when you are looking for comprehensive information on a certain topic.

As an example, a search about the topic "environmental effects of plastic waste".

  • Begin the search by grouping your topic into central subject matters. When brainstorming for search terms you can use a mind map. Do not use very general terms in your search such as effects.
    • Search terms: plastic waste, environment
  • Think about broader, narrower, parallel terms and different types of writing.
    •  litter plastic, plastic bottles, pollution
  • Select the appropriate keywords and form a search string.
    • Combine synonyms and parallel terms, for example, on the same line with an OR operator (Note: Use parentheses in Command search)
    • Connect the subject matters with the AND operator
    • Also use truncation (*) and replacement character (?) if necessary
    • Use a phrase (" ") when you want the search terms to occur consecutively in the search results.

 An example search string:

"plastic waste" OR "litter plastic"


environment* OR pollut*

















In the example picture information has been searched on the environmental effects of plastic waste in Scopus database.
Picture: Scopus <> 13.6.2018



Further information: Command search

​In some databases it is recommended to use a command search (e.g. IEEE Xplore and ACM Digital Library).

First form a search string by using parentheses when searching for information on the environmental effects of electronic waste:

("electrical waste" OR "electronic waste" OR E-waste) AND (pollut* OR environment*)

Once the search string has been formed it is relatively easily transferable into different databases. It only needs to be modified based on the database's instructions if necessary, since e.g. operators, expressing a phrase and different inflections of words usually depend on the database. 


















In the example picture information has been searched on the environmental effects of electronic waste using the command search in IEEE Xplore database. Image source: 25.6.2018