nitpick

Etymology

From nit + pick, originally referring to literally removing invisibly tiny louse eggs by hand.

verb

1. (figurative) To correct insignificant mistakes or find fault in unimportant details.
   Someone will invariably nitpick about any spelling error posted to the forums.
   But Pirates! comes with all the usual Aardman strengths intact, particularly the sense that its characters and creators alike are too good-hearted and sweet to nitpick. The ambition is all in the craft rather than in the storytelling, but it’s hard to say no to the proficiency of that craft, or the mild good cheer behind it. April 26, 2012, Tasha Robinson, “Film: Reviews: The Pirates! Band Of Misfits :”, in The Onion AV Club
2. (archaic, literally) To pick nits (lice eggs) from someone’s hair.