Best treatment for dry curly hair?

[brighthair]

I have v v dry hair which is v curly, and I need some help.
I wash it every 2/3 days, and style it with a mix of argan oil cream and serum. I never brush, comb or blow dry it. I need some mega shampoo, condition or deep treatment that WORKS
Have tried John Freida stuff and that Aussie 3 minute miracle. Nada. In fact, you could probably pour oil on my hair and it would drink it up. Any other not pricey recommendations?

My daughter has very fine, very long, very curly hair, but a lot of it. She went through a stage of straightening it every day, which caused it to break off. And I mean majorly break off, Currently it's lovely and long and very healthy, but she washes, conditions, wraps it in a cotton t shirt, then lets it dry naturally. She also does deep conditioning often. I'd say the trick is not the products themselves, but the fact she only now uses heat treatment when she is going on a night out. She does use products for curly hair.

Personally I think her hair is gorgeous, it's proper cork screw curls to below her chest, but I guess we always want want we don't have and often hers is screwed up in a bun at the back of her head and then straightened for nights out.