The point is that there is a basic weakness which is unprotected in his style. You have to aim for the crotch. If you deliver the blow there, it kills.
13 seconds sound clip from the The Woman Avenger (1980) movie soundboard.
You can hear this line at 01:15:16 in the DVD version of the movie.
Quote context
[...]
- Don't worry. Well sister, I believe that I will beat him.
- Buddha will see that we win in the end. A dupper like that can't win.
- I've thought about this for a long time, but I think it's right you know.
- It's the secret Twin style of boxing. I was sworn to secrecy about it.
- You must defeat Quang Wu Chi, so I have to tell you.
- Sister, you don't have to say things to me like that you know.
- You two think you're so clever.
- I've been looking for you for a month, but now the party's over, you're coming back with me.
[...]