Hi, I'm John Popper, lead singer of the band Blues Traveler. I also play harmonica, and am arguably one of the best in the world. But thank God, there really never can be an actual best, but I'm damn good. I'm gonna teach you a few things about the harmonica.
The way to hit difficult notes on a harmonica is you can bend notes lower by inhaling more. And exhaling low notes is harder to bend. You don't bend as well but, exhaling notes higher that's easier but inhaling notes on a bend, higher is harder to do.
Howard Levy, that harmonica player I told you about, showed me a trick where if you blow into a draw-hole, that note isn't there on a harmonica. That note doesn't exist. You're bending the draw-hole by blowing into it, which is a cool little thing.