i purchased 3 days ago im missing half brushes
ZBrushCore comes with 30 brushes that load with the program by default. If you click on the brush selector button to bring up the brush popup, you should see these in the lower section of the menu ( not in the quick pick section!).
If you don’t see this many brushes, there may be an issue with your installation. You will need to contact Pixologic Support, and start a conversation there.