With great care, search clubs mob organised (4)
I believe the answer is:
comb
'with great care search' is the definition.
(comb can mean to search carefully)
'clubs mob organised' is the wordplay.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'organised' is an anagram indicator.
'mob' anagrammed gives 'omb'.
'c'+'omb'='COMB'
(Other definitions for comb that I've seen before include "Toothed implement - search (the area)" , "Crest on the head of some birds" , "Toothed grooming implement" , "Disentangle" , "Go over" .)