How many movies have Yuen Cheung-Yan and Yuen Yat-Choh acted in together?

They have worked on 19 movies together! Their first movie together was The Boxer from Shantung (1972) while their highest rated movie together was The Miracle Fighters (1982). They have not worked together since In the Line of Duty 3 (1988). They are most known for their action films together.