sentences:  He travelled throughout the country with a group of famous singers and comedians like Siu Black, Thanh Lam, Quang Linh, Minh Thuận, Duy Ngọc, Duy Phương, Hương Loan, Ngọc Thành and his sister Kiều Nhi, and became well-known with the songs ‘Lòng mẹ’ "(Ngọc Sơn)" and ‘Còn thương rau đắng mọc sau hè’ "(Bắc Sơn)".At the age of 14 he had to stop singing for a while, because his voice started changing.At age 19, he made his comeback under his new stage name Nhật Sơn, not singing traditional anymore but Vietnamese POP-music.