Kerastase Anti Hair-Fall Serum

Hii everyone! Hope you're all having a great day 😊

I have a question - I bought this Kerastase serum, and while I don't think it's really doing anything to help as far as fallout goes, I do love it. When I rub it on my scalp it gives my hair more volume, makes it less oily, and makes it really soft.

Is anyone able to shed any light on what ingredient(s) would be causing that? Or if there's anything similar on the market that would work the same way? I don't really want to spend $100 again lol.