Lesson proposed by TRAN QUANG HAI for learning throat singing, 02.2009 17.04.2018 by Hai Tran Quang Lesson proposed by TRAN QUANG HAI for learning throat singing, 02.2009 QuangHai Tran Ajoutée le 22 févr. 2009 Trân Quang Hai presented his exercice for training overtones with the technique of one mouth cavity .