Vovinam to demonstrate Vovinam publicly in Hanoi with his disciples in 1940, Nguyễn was invited to teach the art at Hanoi's Ecole Normale, and Vovinam gained in popularity. During the following years, political unrest increased throughout Vietnam; due to the system's nationalist political orientation, the art came under suppression. By 1954, Nguyễn had emigrated to South Vietnam, where he was able to continue to teach and establish Vovinam schools. After his death in 1960, Grandmaster Le Sang continued the development and international promotion of Vovinam until his own death on September 27, 2010. The first Vovinam school outside of Vietnam was
Vovinam benevolent heart", the student is reminded of the main principle and the goal of Vovinam Việt Võ Đạo with every training. It is also about using the opponent's force and reaction, reaching maximum effect with comparatively little force. The term "Việt Võ Đạo" ("the way (Dao) of Viet Vo") was coined by the patriarch of the second generation of the Vovinam Viet Vo Dao, Le Sang, with the objective of adding a philosophical dimension to his martial art. This "Viet Vo Dao" consists of ten principles: (The wording can vary slightly between Vovinam schools) A "Việt Võ Đạo Federation" was