Can i power a this circuit with 9v?

Bad english ahead Hi, so i'am new in this and i have this problem with a rather simple project, it's a bluetooth controlled car:

-Two 3-6v motors -Arduino UNO -HC-06 -L293D(integrated circuit)

So i'am powering all with 6v and it's working but one of the motors is moving slower than the other, i can change it in the program but i was wondering if maybe the voltage used is too small. Could i use a 9v to power all the circuit? could the motors broke?

If they are 6V motors, then you should run them at 6 volts. But, the Arduino UNO needs at least 7V to function properly.

Also, please read:

And then include all the stuff you left off, so we can better help you.

Don’t forget the ~2.5volt loss in the ancient L293 H-bridge chip.

6volt for the motors means a ~8.5volt supply is needed.
9volt will do just fine.
Can always reduce power with PWM.