Exact vs Flex Search
There are two types of Words searches: Exact and Flex.
An Exact search finds the exact word or phrase entered in the Search Entry box.
A Flex search finds all words containing English grammatical forms, plurals, and singulars of all words rather than exact phrases (unless excluded by quotes). For example, a search for "forgive" would find "forgive," "forgiven," and "forgiving."
When performing a Flex search, anything in quotation marks is treated as an exact search. In this way you can combine a Flex and Exact search.
The default setting is Flex (on). Tap to turn Flex Search on or off and override the default setting.