In the first men's singles rubber, Nguyen Hoang Thien lost to Kareem Allaf 6-7 (3-7), 1-6.
The pressure was placed on 18-year-old Nam's shoulder, as a loss would have meant Vietnam would have lost out on a place in the final.
The youngster had a shaky start, but came from behind to beat his rival 6-4, 6-1 to level the score for Viet Nam.
In the men's doubles, Nam and Do Minh Quan quickly defeated Nour and Marc Abdelnour 6-2, 6-4 to take a 2-1 lead.
In their first match, Vietnam crushed Turkmenistan 3-0.
Vietnam's next rivals will be Cambodia.