The duo lost to Miliaan Niesten of the Netherlands and Francesco Vilardo of Italy 5-7, 6-7(5) in the match, which lasted one hour and 42 minutes.
Other Vietnamese players were also ousted from this division. Pham Minh Tuan and Trinh Linh Giang were defeated by Japanese Sho Katayama and Arata Onozawa 1-6, 2-6.
In other court, Blake Ellis and Michael Look of Australia defeated Daniiar Duldaev of Kyrgyzstan and Jonathan Gray of Great Britain 6-1, 7-5.
In the second round of men’s singles on November 9, Chen of Chinese Taipei crushed his teammate Chien Hsun Lo 6-1, 6-4. Enzo Couacaud of France bested Lukas Ollert of Germany 6-4, 6-2.
While Vasko Mladenov of Bulgaria won Congsup Congcar of Thailand 6-4, 7-6. Japanese Rio Noguchi beat his teammate Sho Katayama 6-4, 6-4.
The event, which has a total prize of US$15,000, will finish on November 12.