Which dog food is a better choice?

Hello all!! I am an avid dog lover and I own small dogs. To be exact, I have a Chiauhauha, two Jack Russell Terrors, and a Dachshund. I am trying to provide them with a good, healthy dog food. I want their dog food to contain high quality products that are easy for them to digest. I have tried them on two different brands and am wondering which one to keep them on. I have tried then on Purina One Beyond Dog food and Blue Buffalo Chicken and Rice Small Breed dog food. Which one is the better choice? Also, can anyone point me in the direction of reliable and valid dog care resources?