If the Philippine passport holders want to apply visa at Vietnam Embassy, they should to know that:
Visa administrative Institution: Vietnam Embassy
Processing time: depends on you how fast you need. But for sure, you should make a call to Vietnam Embassy for details.
Required Documents: passport, money and 1 new envelope with stamp on it and your exact home address in order to avoid losing issues.
How to apply: please take a look at contact information of Vietnam Embassy below
EMBASSY OF VIETNAM IN PHILIPPINES
Address: 670 Pablo Ocampo, Malate, Manila, The PHILIPPINES
Phone: (632) 521 6843
Fax: (632) 526 0472