Khoi, seeded atnumber 13 in the competition, now tops the group with eight points. Heis one point ahead of Ukraine's Viktor Matviisen.
Histeammate Nguyen Quoc Ky defeated Karanvir Lutchman Singh of Wales,but may miss out on the chance for a medal after only accumulating 3.5points in the eight rounds.
Other Vietnamese players arealso struggling at the tournament. Nguyen Thi Mai Hung overcame BogdanaNonkovic of Serbia in the girls U18 event to reach a five pointtotal.
In the boys' U16 event, Le Tuan Minh earned one more pointafter defeating Henning Kjoita of Norway, while Tran Tuan Minh lost toTomas Laurusas of Lithuania and remained on 4.5 points.
Tran Minh Thang and Nguyen Dang Hong Phuc both lost their latest gamesin the boys' U12 event. They were beaten by Iranian rivals ParhamMaghsoodloo and Aryan Gholami respectively.
The ninth round of the competition also began on November 17.
Meanwhile, Vietnam 's grandmaster Le Quang Liem triumphed over DasDebashis of India in the third round of the Fujairah InternationalChess Championship. The result means he now has two points and placeshim tenth in the rankings.
Liem was back in action for the fourth round on November 17.-VNA