hey, so when i first got my pup(8.5 weeks old), ill admit i just bought some dog food from target(purina maybe), and he was fine on it for few weeks until he ate something one day and got sick and the vet had me switch him to boiled chicken and rice for a little while. I took advantage of this time to switch my boy to a better dog food. I purchased taste of the wild, sierra mountain formula(lamb)., i slowly started weening him off rice and chicken, starting off with only 1/2 a cup for 3-4 days(4x a day), 1 cup for 3-4 days, 1.5 cups 3-4 days, then moved him to completely on kibble.
As of right now, hes 15 weeks, and eats between 1.5-3 cups per sitting(i let him eat for max 10 min or until hes bored with it, but usually finishes rather quickly) 4 times a day.
To say the least..he still has the runs, and hes been introduced to the new food since november 24. As of a few days ago, i started doing 2 cups of kibble, mixed in with water and some rice, and its been making his stools a lot more firm, but not 100%.
Do i need to switch dog foods? or should i just stick with it? Im open to all suggestions what to do/what type of food i should put him. Should i just keep putting some rice mixed in with his kibble, or should i try something else?
thanks(im also talking to my breeder and vet, but love as much input as possible, just want this fixed

!)