The text search engine allows queries to be formed from arbitrary Boolean expressions containing the keywords AND, OR, and AND/NOT. See the examples below.

Example 1:

individual protection
finds documents containing the phrase individual protection

Example 2:

individual AND protection
finds documents containing individual and protection in different or the same field (abstract, title, etc.)

NOTE:

Examples 1 and 2 will produce different results. In example 1 the PHRASE is being searched, not the individual terms. Example 2 provides the broader search results.

Example 3:

individual protection OR collective protection
finds documents containing the either the phrase individual protection or the phrase collective protection

Example 4:

individual AND protection OR collective AND protection
finds documents which contain the term protection and either of the terms individual or collective.

Example 5:

(individual AND NOT collective) AND protection
finds documents containing protection, plus individual but not collective

Example 6:

prote*
finds documents containing terms starting with prote (protection, protest, protease, ...) This can be a powerful tool; however, it can also bring back many search results that are unrelated to the results you are asking for.

This figure identifies the difference between AND, OR, and AND NOT. Set 1 is the colored oval and Set 2 is not colored.