Boolean operators must be written in all capital letters
[space]
Find documents with all the words specified. dopamine homeostasis will get documents with dopamine and homeostasis, found documents must contain the two elements.
OR
Find documents with at least one of the words specified. dopamine OR homeostasis will get documents with word dopamine or homeostasis.
-
The sign - exclude the documents with word or expression specified. dopamine - homeostasis will get the documents with dopamine but without homeostasis. The sign - must be used with others operators.
" "
Find the documents with exactly the expression between the two quotation marks.
Example: "symptomatic medication" will find only the documents with "symptomatic medication" in the document.
( )
Brackets are used to group words in a sub expression: (dopamine homeostasis) OR (ergotamine headache)
*
Asterisk is the truncation operator. It can be used as a prefix (with quotation marks) or suffix. dopa* homeo*, dop*ne or "*cature".
