In EBSCO Discovery Service (EDS), stop words are generally disregarded by the search engine. For example, when you search for the word “the” by itself, no results should be returned. Stop words are commonly used words such as articles, pronouns and prepositions.
There are some exceptions for searching stop words. For instance, "a" is a stop word for most databases but not for music databases, (example search: Piano Concerto A minor). And "p" is a stop word for most databases but not for medical databases, (example search: genome mapping P alba, P deltoides, P euramericana). So if either of those stop words are searched in an EDS profile that has music and medical databases, results will be returned.
Typically, when a phrase is enclosed by double quotations marks, the exact phrase is searched. If a phrase contains stop words, the stop words will not be searched, but the searchable words will be searched in the order as entered. A stop word will never be searched for in an EBSCOhost database, even if it is enclosed in double quotation marks. A search query with stop words only (i.e. no other terms) yields no results.
When Boolean operators are included in a phrase search that is enclosed by quotations marks, the operator is treated as a stop word. When this is the case, any single word will be searched in its place.
If you enter phrases with punctuation, the search engine searches for the term both with and without the punctuation. For example, if you enter television: talk show, the search engine finds results with television talk-show, television talk show, and if synonyms have been activated, TV talk show.
If you enter hyphenated words in a search, the search engine automatically searches for the word in both hyphenated and non-hyphenated forms. For example, entering coca-cola will find both Coca Cola and Coca-Cola.
If you are searching for a title that ends in a question mark, the symbol should be removed from the search in order to ensure results will be returned. The question mark symbol is treated as a wildcard when searching the EBSCOhost databases.
Boolean logic defines logical relationships between terms in a search. The Boolean search operators are and, or and not. You can use these operators to create a very broad or very narrow search.
Notes:
The following table illustrates the operation of Boolean terms:
| And | Or | Not |
| Each result contains all search terms. | Each result contains at least one search term. | Results do not contain the specified terms. |
| The search heart and lung finds items that contain both heart and lung. | The search heart or lung finds items that contain either heart or items that contain lung. | The search heart not lung finds items that contain heart but do not contain lung. |
When a single Find field is displayed, you can enter search terms in the Find field, and combine with AND, OR, and NOT. (For example, Roosevelt NOT Franklin.)
When Guided-Style Find fields are displayed, you can enter search terms in each Find field, and select AND, OR, and NOT from the Boolean drop-down lists.
With longer search strings, you can combine many terms in a search with the AND operator, which will narrow your search results. For example, heart AND lung AND bypass AND artery will provide a more focused search than heart OR lung OR bypass OR artery.
To make even better use of Boolean operators, you can enclose search terms and their operators in parentheses to specify the order in which they are interpreted. Information within parentheses is read first, and then information outside parentheses is read next. For example, (heart OR lung) AND bypass will return different results than heart OR lung AND bypass.
To make even better use of Boolean operators, you can use parentheses to nest query terms within other query terms.
You can enclose search terms and their operators in parentheses to specify the order in which they are interpreted. Information within parentheses is read first, then information outside parentheses is read next. For example,
When you enter (mouse OR rat) AND trap, the search engine retrieves results containing the word mouse or the word rat together with the word trap in the fields searched by default.
If there are nested parentheses, the search engine processes the innermost parenthetical expression first, then the next, and so on until the entire query has been interpreted. For example,
((mouse OR rat) AND trap) OR mousetrap
When Boolean operators are contained within a phrase that is enclosed in quotation marks, the operator is treated as a stop word. When this is the case, any single word will be searched for in its place.
From EBSCO Support.