You may have already done so, but a hair analysis could also be helpful.

For a good two years now nothing worked for me, but recently I found out I was low porosity so nothing was getting into my hair.
Hair type: 2C-3A, very dry, extremely low porosity, med elasticity, insanely thick kinky-wavy.
HGs: Trader Joe's Nourish spa conditioner, Epsom salt rinse, Joico K-pak conditioner