A lot of the dumbbell exercises target the areas you're talking about
How is this possible?
Muscle and fat are independent of each other. You can build muscle in a specific area, but you can't remove fat in a specific area other than by surgery.
For the OP, if the problem is back fat/side fat around the bra band, a bra with more hooks might help. If your breasts are coming out of the top or sides of the bra cups, you need a bigger cup.