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Using Resources

Search strings

Constructing a search string: keywords and operators

Adding special characters and words, known as operators, gives the search engine more precise instructions on how to search and so provides you with more relevant results.

The choice of operators to use depends on the nature of the keywords you have identified:

  • A proper name or a distinct phrase
    If you have identified a distinct phrase, you will want the search engine to find documents that contain only that exact phrase. The common way to specify a phrase is to enclose it in double quotes eg "native american"

  • Words with multiple meanings and contexts
    To make your search specific you need to search for documents that include every one of several words. To do this use the Boolean AND operator. Search engines commonly use this operator by default, so often you do not need to put this operator in the search string.
    For example: children AND poverty AND Africa.
    Often a document will only be relevant if two or more of your keywords are close to one another. You can specify this in your search string by using the NEAR operator.
    For example: william NEAR gladstone would match William Gladstone, William Ewert Gladstone, William E Gladstone and Gladstone, William Ewart.

  • Synonyms and spelling variations
    To ensure the search engine retrieves documents with any one of your variants, use the Boolean OR operator.
    For example: "red indian" OR "native american"
    Some spelling variations can be accounted for by assigning the wildcard operator to allow variation in one character.

  • Words with many possible endings
    To tell a search engine to search for all the words derived from a common root, use the truncation operator.
    For example: femin* will match feminism, feminist and feminine.

  • Words you want to exclude to prevent irrelevant results
    To ensure any documents including such a word are excluded from your search, use the Boolean AND NOT operator.
    For example: "special education" AND NOT hyperactivity

Internet search engines do not usually support as many search features as the search engines in subscription databases. For example truncation is not commonly available in Internet search engines. Check the help pages for any search engine you use to find out what features are included, and how you can use them. You may find the search engine features chart at Search Engine Watch a useful guide to the operators supported by popular Internet search engines.

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