Vietnamese Traditional Folk music album by Tran Quang Hai in 1988. This is a solid album and a good introduction to Vietnamese Folk music. It even got a 4.5/5.0 on allmusic.com. Give it a try, you'll probably like it.
Tran Quang Hai, a virtuoso of the dan tran zither as well as many other instruments, is also a well-known author and researcher. Singer Bach Yen started professional life as a Saigon pop singer before she went to Paris to study voice. Both have been working for years outside Vietnam: Bach Yen sings in Hebrew and several European languages as well as Vietnamese, and Tran Quang Hai's playing shows clear, though intermittent signs of influence by European harp playing. As you'd expect, their performances are colored by these experiences in a personal way that is rather different from the customary intercultural cross-fertilizations.