Hyol Do Bup is a the name of the nervepoint system in the Korean martial arts like Sin Moo Hapkido

Sin Moo Hapkido

Sin Moo Hapkido is a martial art that combines "hard" and "soft" techniques. It is closely related to its parent art, Hapkido, though it places more emphasis on meditative, philosophical, and Ki development training. Hapkido is often translated as “the way of coordinating power,” which places...

 and Hanmudo

Han Mu Do

Han Mu Do, founded by He-Young Kimm, is a martial arts system consisting of the study of empty hand techniques, the study of weapons, the study of ki, and the study of martial arts philosophy.- Origin :...

.
Learning these techniques has multiple purposes like healing, preventing various aches over the body and attacking.

These techniques are usually only taught to advanced students.

Other Korean martial arts, like Hankido

Hankido

Hankido is a new hapkido style developed by the late Myung Jae Nam using even more circular flowing movements owing to Nam's background in traditional Korean dance.-Etymology:...

sometimes refer to these techniques as Su Chim Do Bub (수침도법).