male miniature schnauzer too skinny

by Jane
(Malaysia)

I wonder why my male miniature schnauzer is so skinny that you can even seen a curve shape of his body.

I've observed him to eat kibbles mixed with dog canned food and finished it all the time.

He is very healthy and poops well but still very skinny.

I have discussed with my veterinarian and changed to high protein dog food but it seems not to be working.. still skinny.

Do you have any solution for this problem?

Waiting for your reply.

Thank you.