Search thoroughly (4)
'search thoroughly' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for comb that I've seen before include "Used to tidy hair" , "Device with teeth - store for honey" , "Common hair tidier" , "Search methodically" , "Groom the tresses" .)
(Other definitions for rummage that I've seen before include "Search unsystematically" , "Search haphazardly" , "Type of sale" , "Ransack" , "Unsystematic search" .)
'search thoroughly' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for trawl that I've seen before include "Net for fishing at sea" , "Large net used for fishing" , "Fishing-net" , "Use net" , "Comb" .)