Nhi overcame Jackeline Perez of Peru to win the semi-final round for the first time.
The third-placed competition saw the Vietnamese cueist play Charlotte Sorensen of Denmark who dominated the game in the initial minutes. Nhi narrowed the gap to just 14-11 before Sorensen scored consecutive points to win the match 30-15.
Yen Nhi, together with Karina Jetten of the Netherlands, shared third place with a cash prize of US$4,400.
Elsewhere, her teammate Phung Kien Tuong failed to get any medal at the tournament.
The UMB World Three-cushion Championship is a professional Three-cushion billiards championship which was first held for male players in 1928 and for female players in 1999.
This year the tournament for women was organised in Blois city, France, from September 10 to 12.
VOV