You have to breathe through them rather than blow. I couldn't describe how you get the notes but you do. Move your mouth about a bit, shift your tongue, blow out your cheeks, you'll get it eventually. Strangely some Italian friends of mine gave me a Jew's harp which was the best I've ever had. When my first wife left me she took it with her. She was a pianist. Never could figure. Maybe she didn't want me to inflict on some one else?