I'm having the exact same problem haha. I'm very new to the game and I wanted Hazama to be my main but I am just getting destroyed online. I've practiced all the BnB combos but in a match I get lost also. I feel like unless you can pull off those combos perfectly he doesn't do enough damage.
I'm gonna take the advice and try someone else out to learn the ropes better, but I still want to get better with him.
If you're on PSN doublethink, add bike_tough if you wanna practice sometime.