other fish to fry
Mais Nabot avait d'autres chats à fouetter.
But Naboth had other fish to fry.
— La Cité de Dieu (2002)
On a d'autres chats à fouetter.
We've got other fish to fry.
Ils ont d'autres chats à fouetter, crois-moi !
They have other fish to fry, believe me!
— Independence Day (1996)