Saw a kung fu movie with a caucasian brother and blond haired sister kung fu fighters with their chinese friend (his stage name in the movie was li the ) and they are forced to fight each other in an arena blindfolded. Also if I remember there was this very huge chinese guy that the white kung fu guy fought and killed by thrusting his stiffened fingers right through the big guys chest or stomach. Another scene I remember is the white kung fu fighter's sister (blond hair) fought three chinese men who attacked her in a room, 2 of them holding her on either side whilst the third man came up to her from the front. She kicked the frontal chinese guy and threw the other 2 over her shoulders. That is all I can remember. Can you help me find this movie ? I think it was between 1979-1984