As you noted the main differences already - Scolopendra subspinipes "de haani" (Vietnamese centipede) has orange legs and the Scolopendra subspinipes "Mau Chai" has yellow. The main differences you will find between like species that differentiate one from another, other than colors, will be location of origin.
Both centipedes belong to the same ssp. of Scolopendra subspinipes dehaani. Despite the fact that they belong to the same ssp., they might be looking entirely different. As Cheetah already pointed out, the Mai Chau locality (a valley in Vietnam, google it for some pictures, it's a nice place) S. subspinipes are overall brown with yellow legs (and sometimes red terminal legs). The "Vietnamese" centipede (probably the other color morph found in Vietnam) is overall brown too but has orange legs.
There are also other morphs of S. subspinipes dehaani such as the "Chinese Giant" which is overall red in coloration.