Search Modes:
with ALL of the words: returns hits that CONTAIN all of the query words in any order.
with EXACT PHRASE only:returns hits that CONTAIN the exact query phrase.
matching REGULAR EXPRESSION: returns hits that contain the query words, even as a substring.
For example, if searching on phosphate, bisphosphate would match.
with ANY of the words:returns hits to any word in the query phrase.
with the EXACT PHRASE ONLY:returns only those hits that exactly MATCH the query phrase.

Additional search options (Extended Searches only):

!= : returns hits that do NOT MATCH query phrase.
with no value: returns hits for which the selected field of a given class has no value.
For example, a search on Reactions for which the field CatalystActivity has no value will return all reactions that donít involve catalysts.
with any value: returns hits for which the selected field of a given Class has any value (not zero or blank).