Question: What nationality is Nguyễn Thị Ngọc Diễm's husband?
Sentence (from "Trịnh Doanh"): Trịnh Doanh (4 December 1720 – 15 February 1767) ruled northern Vietnam (Tonkin) from 1740 to 1767 (he ruled with the title "Minh Đô Vương").
Relevant evidence: Yes