I know how you feel. I thought dog food what the way to go in beginning. Quick, Simple, Easy.....
Well, I guess Roxy and TJ didn't get that memo
So like you, I tried numerus different brand, dry and wet, had to sprinkle cheese on top or a liver treat and it was still like pulling teeth to get them to eat. Then I start to mix home cooked with smashed up kibble, this worked better than just plain kibble, but it was still work and there were many times that I still had to add a *topper* to get them to eat.
After a little research in the RAW feeding, I decided to give it a try. I bought the Nature's Variety Frozen Medallions. WOW - it was gone so fast I wasn't sure if they ate it or if it magically vanished
(Mine liked them still a bit frozen, so I would place the portions on a piece of clear wrap on the granite counter top for about 7 mins. just thawed enough for me to cut them up into little bit size pieces. This also was good b/c they had to chew it and it was kinda cleaning their teeth)
Anyway, I honestly do believe that RAW is the BEST for them, however, if your dogs has liver issues (like mine, that's why I am back to home cooking) than it's not good for their livers to digest that type of protein and organs.
Best of Luck.
You can go to the Nature's Variety website and read about the RAW frozen food