Go through fabric stiffener when time is key (6)

I believe the answer is:

I'm a little stuck... Click here to teach me more about this clue!

'go through' is the definition.
(I've seen this in another clue)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for search that I've seen before include "Chaser (anag)" , "Fish about" , "Explore" , "investigation . . . ." , "Look carefully (for)" .)

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app