scratch your head
scratch (one's) head
To show that one is puzzled, doubtful, or uncertain; to show that one has trouble understanding something. Literally scratching one's head can indicate the same thing. His decision to pull the plug on the lucrative program has everyone scratching their heads.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
scratch your head
1 think hard in order to find a solution to something. 2 feel or express bewilderment. informalFarlex Partner Idioms Dictionary © Farlex 2017
scratch your ˈhead (over something)
think hard in order to find an answer to something: We’re all scratching our heads for a solution to this problem.Farlex Partner Idioms Dictionary © Farlex 2017