Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
vu khac » vu kham, vu khanh, bui khac
nang xa » nang x, lang xa, nang ma
hoc van » hoc dan, hoc va, hoc vat
tac van » tac vang, cac van, tac va
vi ve » va ve, gi ve, vi he
ve ve » de ve, va ve, ke ve

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu khac ky nang xa hoi. hieu vien cac ((hoc van) or (tac van)) hanh ((vi ve) OR (ve ve)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu khac ky nang xa hoi. hieu vien cac ((hoc van) OR (tac van)) hanh ((vi ve) OR (ve ve)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu khac ky nang xa hoi. hieu vien cac ((hoc van) or (tac van)) hanh ((vi ve) OR (ve ve)) triet".
• Adding a wildcard symbol may retrieve word variants: vu khac ky nang xa hoi. hieu vien cac ((hoc van) or (tac van)) hanh ((vi ve) OR (ve ve)) triet*.