Clubs in 'tart search' (5)
I believe the answer is:
scour
'search' is the definition.
(scouring is a kind of searching)
'clubs in tart' is the wordplay.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'in' means one lot of letters goes inside another.
'tart' becomes 'sour' ('sour' can be similar in meaning to 'tart').
'c' put inside 'sour' is 'SCOUR'.
(Other definitions for scour that I've seen before include "Clean by hard rubbing" , "Scrub clean" , "Look high and low" , "Rub with a gritty substance" , "Clear out" .)