Double quotes around part of a query means make sure this part is actually matched in the index. (I think they still annoy me be including sites that are linked to using this phrase[2], but that is understandable.)
Then there is the "verbatim" setting that you can activate under search tools > "All results" dropdown.
[1]:And the reason they annoyed me was because they would still fuzz my queries despite me doublequoting and choosing verbatim.
[2]: To verify this you could open the cached version and on top of the page you'd see something along the lines of: "the following terms exist only in links pointing to this page."