<< I have like 120 volumes of one archive, and one of the volumes is broken, b/c it extracts only first 32 volumes >>
WinRar has a built in utility that should take care of this for you. You get to the utility as follows:
Commands --> Repair Archive
Point to the file that has the problem and let it do its work. I've been successful at repairing one file that I had which was corrupted, but I was unsuccessful at repairing another one.
Good luck!!