The French colonialists' investigation and scrutiny of Nguyễn Ái Quốc (1919-1931) -- The arrest of Nguyễn Ái Quốc, the subsequent legal case and Nguyễn Ái Quốc's departure from Hong Kong -- President Hồ Chí Minh, the people of Việt Nam, and the Loseby family (from 1933 to the present).