thanks to all of you.
The subtle hair were actually very simple, its just huge amount of very short and very thin hairs.
sandpiper: sure, i can share at least the little i learned with this project, there are 15 layers of hairs,
i used geometry with max standard shader for hair rendering, because i have better results with it, than i did with buffer method, it gives me better volume in render, but it could be just me. i rendered in scaneline because of the speed and used texture information for color variation on hairs. Then i made other render with buffer method and hair&fur shader and mixed it with the geometry hairs in ps to get some specular to it 
I tryied also mental ray with MRprim and hair shader, but it seemed to be so slooooow. It was like hours for render which took just few minutes with fisrt method. But i think the result could be very nice, if i tweak it for some time, it was just too slow for details i needed, but i will use it later for some less detailed render.
and at the end, i used ambient occlusion pass, but for this detail, it took ages to render, so i had to put down AA and AO samples to have some reasonable speed lol