Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Vietnam to Moscow as you normally would.
Aeroflot is one of the carriers that may have flexible change policies. You can use our site to filter for other airlines that may also have this kind of flexibility.
The most popular flight routes from Vietnam to Moscow are Hanoi Noibai - Moscow Domodedovo, Hanoi Noibai - Moscow Sheremetyevo and Hanoi Noibai - Moscow Vnukovo.