I think that your diet has a big influence on the state of your hair. And apparently you need to use a pH balanced shampoo. One hair dresser said that the shampoo should be runny in your hand. If it all "clumps" together, and you can pass it from one hand to the other in one big "glop", not a "trickle", then it has too much wax in it, and that will make your hair gunky and dull.
But I read about a hair conditioner that is apparently great for getting smooth, shiny, silky hair. It is not great for fine limp hair, but if your hair is relatively thick, with a bit of "substance" or body, then it's supposed to be good! You just take an avocado and throw it in the blender with a tablespoon of olive oil, blend it smooth, and rub it through your hair, especially at the ends. Wrap your hair up in a towel and leave it for 1/2 to 1 hour, then rinse out, and if you feel you need to, use a really gentle shampoo on it (maybe a baby shampoo?). I haven't tried it myself, yet, but it sounds easy enough and not too expensive to try! HTH!