Vietnam coach Henrique Calisto rested four key players for the decisive match against Malaysian on December 6.
His makeshift team met difficulties in breaking down the weak East Timor squad in the first half.
Calisto proved his ability in the second half with some tactical changes and captain Mai Tien Thanh needed only eight minutes to rearrange the new team to score the opening goal after the break .
Four minutes later, he doubled the score with his header when receiving the ball from the left wing.
The third goal went to Phan Thanh Binh while Thanh scored a hat trick in the game.
With one win and one draw, Vietnam now shares top position with Thailand in group A with four points.