Try not to feed him people food, or he won't eat his kibble. Lol My Mimi girl was very finicky. She would eat the kibble only if i mixed something yummy, like plain boiled chicken, plain salmon, plain scrambled eggs, I've tried many things that's ok for her to eat, trying to entice her to eat. Then she would only pick & eat the yummy things & not touch her kibble!
I've also tried numerous different premium kibble, which btw you can ask for samples. Just go to the sticky in the health & diet section, they have a list.
The only kibble she likes & still likes is Natural Balance Sweet Potato & Venison. Although I still have to mix in something
, she's still eating it.
Some dogs are genetically built thin, if the vet says he's healthy, I wouldn't worry too much about his weight. What did the vet say?
Good Luck & I hope you'll find the one he'll like.