Firefist of Incredible Dragon(1982)

The plot is about a bloodthirsty lord called Pi Hao who have young girls kidnapped to satisfy his lusty desires. He orders the killing of Shao Shao, one of the young girls, and his henchmen burry her body in the forest. Her sister Sho Kown goes after her and - as the two sister were very much look-alike - Pi Hao send his men to check the place where the body is buried. But the grave is empty and all the men who were sent to burry it are found dead...