Name of ethnic group: San Diu (San Deo, Trai, Trai Dat, and "Man Quan Coc" (Man in Shorts)). Population: 126,237 people (Year 1999). Locality: The San Diu live in the midlands of Quang Ninh, Hai Duong, Bac Giang, Bac Ninh, Vinh Phu, Thai Nguyen, and Tuyen Quang provinces.