Blow harder. I got one for Christmas. It frustrated hell out of me until I realized that there are four notes, doh re mi fah, at the bottom of scale and then a gap until you hit the next doh. With practice after that you should be able to get doh re mi fah, soh lah ti doh re mi fah and soh. My fingering chart says "The five overtones are generated by keeping all three finger holes closed and blowing progressively stronger with a sudden, attacking release of air."