Vietnamese players on July 12 defeated Australia 3-0 at the Army Stadium in Phnom Penh, Cambodia.
Nguyen Huu Thang opened the scoring 17 minutes into the game, and Tran Van Dat made it 2-0 10 minutes later. Nguyen Khac Khiem concluded the game with his goal in the 78th minute.
Thang and Khiem have netted two goals each in this group round.
Vietnam have six points after the second win and have kept a clean sheet for 180 minutes.
Vietnam lost 0-1 Australia in the Asian Championship qualification last September.
They will have one day to rest before returning to the field against Myanmar on July 14.