@Mim_ This is one of those idiotic, boring levels. there is really nothing you can do except keep eliminating bombs until the yellow bomb arrives at the bottom, then you have to immediately combine it to eliminate the keys. after that you have 7 moves to eliminate all the jelly. I guess I was lucky enough to keep eliminating the bombs until the yellow bomb arrived. I still needed a hammer to finish the game.
Unfortunately, I can't give you any tips in what is a poorly designed, mundane level. I feel for you.
Good luck,
Peter