Perhaps you should try some spelling variations:
hieu vien » hieu hien, thieu nien, hieu tieng
hieu viec » nhieu viec, hieu ve, sieu viet
may nang » may nong, ky nang, cam nang
tu sach » thu sach, su sach, te sach
cao tuc » dao tuc, cao duc, cao suc
hanh de » hanh ve, hanh kem
va nang » van nang, da nang, cam nang
va hanh » van hanh, va thanh, va danh
de cua » le cua, te cua, dieu cua
tuc va » thuc va, truc va, tuc xa
cua te » cua tu

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

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