Diet for dogs requires practice and a lot of research. Bags of dog food off the grocery store shelf are usually liste as "complete nutrition" but are filled with bad ingredients like corn, by-products, and insufficient protein sources. It also depends on what kind of dog you have (large dogs need more joint supplements whereas little dogs need more carbs) and what age (active working dogs need more carbs than do overweight or senior dogs).
What I found works best is soaking a dry holistic kibble in water and a drop of olive oil and feeding that. Often I'll mix in dusted (ground up) seaweed [it's important to grind it up otherwise it can get stuck in their intestines] and a canned variety of holistic wet food.
Holistic and raw diets are becoming increasingly more popular as dog owners realize the needs of their companions. They mimic the natural diet and needs of the canine genus (is canine a genus??) and are usually impressed with the results.