Complex sentence: During French rule, between 1925 and 1933, nearly 600,000 Chinese immigrated to Vietnam, ans in the Second Sino-Japanese war, 1937-1941, many Chinese left for South Vietnam.
Split into simpler sentences: During French rule between 1925 and 1933, nearly 600,000 Chinese immigrated to Vietnam. In the Second Sino-Japanese war, 1937-1941, many Chinese left for South Vietnam.