Sorry to tell you that it is hard for a Filipino applicant to get a China visa in a third country if you are not reside or work in the country, but you can have a try at the Chinese embassy/consulate in Vietnam, as I know, the China Consulate in Ho Chi Minh City issues China visa to applicants who are tourists in Vietnam, the China embassy in Hanoi issues China visa to Vietnamese and applicants who work or reside in vietnam.