i just turned 16 and i only weigh 130 pounds and im 5' 11'' i have a six pack but my lower ribs show and ive tried a bunch of differant ab exercises but they still show is there anything i can do about this.

And because of this i fear taking off my shirt because they stick out and when i do take off my shirt people stair at me and all my friends call me rice because they say im actreamly skinney but as ive heard on hear before you dont need muscle mass to be strong.