Bombs

Recently, I came across a wonderful puzzle. The puzzles goes like this. You are given some (let's say m + n) bombs. Each bomb has a push button, bomb explodes by pushing that button. A bomb is faulty if it's push button is jammed, so it's of no use. Every faulty bomb can have only one defect and that is jamming of it's push button, otherwise bomb works. Now assume that some of these bombs are faulty (let's say m)and some are working (let's say n). Can we devise a strategy to get at least one working bomb from these n working bombs?. If we can't do it for sure, can we devise a strategy such that probability for getting a working bomb is maximum?