Perhaps you should try some spelling variations:
hieu vien » hieu hien, thieu nien, hieu tieng
hieu viec » nhieu viec, hieu ve, sieu viet
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
sach ty » sach y, sach tu, sach thu
cac tac » cac toc, cac bac, cac dac
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
vu sach » vu bach, su sach, vu khach
tac va » tac da, tac xa, tuc va
vi cua » di cua

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

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