How to improve hair health?

[image] my hair on pic, has anyone have similar type? If so which products do you use to keep it healthy? Or any other suggestion how to improve it.
So far I am using shampoo and condicioner with caffein and leave in condicioner from Czech brand Bione which is without parabenes, and sulfates. Then from time to time coconut oil. And always airdry it. 1-2x per week but it is still not that healthy how I wish. Dealing with bad split ends and knots. Any help and advice is welcomed.