Your throwing distance seems to be very short.
I always make my own throwing knife. I always carry 3 throwing knifes with me (where firearm is not allowed). When I trained my knife throwing, I would
- walk away from my target for 10 to 12 steps.
- turn around,
- drop down, and
- throw my knife.
I like to throw my knife when I turn around. This way I have less time to aim, and I have to make a quick decision. I also like to drop down to make my own target smaller.