Having a bit of a thin time, this helps (4)
I believe the answer is:
hint
'having a bit of a thin time this helps' is the definition.
The definition suggests a singular noun which matches the answer.
'of a thin time this helps' is the wordplay.
'this helps' says the answer is hidden in the clue (I've seen 'helping' mean this (a helping or portion of the letters)).
'HINT' is hidden within 'of thin time'.
Can you help me to learn more?
(Other definitions for hint that I've seen before include "Tip-off" , "Taste" , "Indicate indirectly" , "signal" , "Indirect clue" .)