There could be many factors that contribute to dry hair. Maybe there is a drying chemical in your shampoo, or maybe you are shampooing too much and it is stripping your hair. Maybe you should go with a thicker oil or try a solid grease. That usually works. And if that doesn't work, try a liquid moisturizer. What could really help is making sure hair is getting good oils - coconut oil for sure, castor oil, extra virgin olive oil, canola oil, lavender oil, rosemary oil are some examples. Just try different strategies until you find what works best for your hair.