Tell too many tales to make cover (7)

I believe the answer is:
overlie
'cover' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for overlie that I've seen before include "To cover up" , "Put in position superior to" , "with crushing effect" , "Sit on top of" , "Rest on top of" .)
