Those bombs suck. I used to basically run in, trigger them all, see them gather (trap or pulls can be really useful), maybe hit them once or twice, then run out. They should bomb where you were. I could usually kill the group before anyone tossed another bomb. If you take longer to kill, remember the run-in-run-out thing. With bow, just run around them, maybe from one side to other, so you can cover the group with your nox.