When users start making use of Boolean search it is a bit like Pandora and that pesky box — as in it is a source of potential unforeseen trouble. Users have no idea what they are getting into until they are already using it; they have no idea what they are missing and get frustrated at the results being continuously broad or too narrow even though sophisticated search terms are used.
This article was originally posted at:
https://medium.com/next-century-user-experience/the-dreaded-boolean-search-413fa757a81c