Find a small quantity (5)
I believe the answer is:
trace
I believe this is a double definition.
'find' is the first definition.
(I know that trace is a more specific form of find)
'a small quantity' is the second definition.
(I've seen this before)
(Other definitions for trace that I've seen before include "Small quantity; find" , "Follow and find" , "Outline" , "Pinch" , "Hunt down" .)