Leung Sheung (Leung Seung) started training in Wing Chun under Yip Man in Hong Kong in 1950. He was in his early thirties and already well versed in a couple of other martial art styles. Leung Sheung was working as president of the H.K. Restaurant and Beverage Workers' Union when he heard about Yip Man from the secretary of the union, Lee Man. Upon meeting the great man, however, he became sceptical of his ability because of Yip Man's short stature.
Yip Man challenged him to a spar. As soon as Leung Sheung charged in to attack him, Yip Man simply and calmly raised his arm. The force threw Leung Sheung to the floor.
Leung Sheung, together with Lok Yiu and six others who later stopped training for various reasons, immediately asked Yip Man to accept them as his disciples. Leung Sheung, Lok Yiu and Chu Shong Tin all lived with Yip Man for several years while learning Wing Chun. It is most likely that this is how the term 'closed door student' came about.
Leung Sheung was a chef in a Chinese restaurant. Later, having learned Wing Chun for many years, he set up his own school in Ho Man Tin and taught Wing Chun professionally.