Perhaps you should try some spelling variations:
hieu vien » hieu hien, thieu nien, hieu tieng
hieu viec » nhieu viec, hieu ve, sieu viet
va triet » va thiet, va trien, ve triet
hanh cac » hang cac, hanh cat, nhanh cay
sach ky » sac ky, sach y, sach ty
hanh ca » hanh cat, hanh cua, hanh cad
nang xa » nang x, lang xa, nang ma
su sach » so sach, vu sach
luc va » duc va, tuc va, loc va

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

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