Im wondering whats the best food to feed my chihuahua?

i have a 6 month old cihuahua im currently having a daily battle with getting him to eat !! Intially when i bought him at 9 weeks old he was on royal canin dry food but i didnt think he liked it !! so i changed it to pedigree chum puppy food which for a whilee he seemed to love !! Although now he doesnt touch it , yesterday i bought him some ceaser puppy foodwich he seemed to love also bought him some fresh cooked chicken which he also loves the problem is im currently unemployd and fresh chcken and the dearer puppy food is something i cant always afford so im just wondering if anyone had any good tips for me on what i can feed my 6 month old male chihuahua without breaking the bank !! I dont want my puppy to have to suffer nutritionally i want im to have the best nutrition possible so please help how can i feed him the best jus on a smaller budget if you know of somegood nutritional brands etc id be so gratefull of help ... Thanks so much !!