Perhaps you should try some spelling variations:
hieu vien » hieu hien, thieu nien, hieu tieng
hieu viec » nhieu viec, hieu ve, sieu viet
hanh dai » hanh tai, hanh dao, vanh dai
vu sach » vu bach, vu khach
cac luc » cau luc, coc luc, cac nuoc
su sach » so sach
ly hang » ly quang
hang xa » hoang xa, hang va, hang ca
va hanh » van hanh, va thanh, va danh
luc va » duc va, tuc va, loc va
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: ((vu sach) or (su sach)) ly hang xa hoi. ((hieu vien) OR (hieu viec)) cac luc va hanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (su sach)) ly hang xa hoi. ((hieu vien) OR (hieu viec)) cac luc va hanh dai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) or (su sach)) ly hang xa hoi. ((hieu vien) OR (hieu viec)) cac luc va hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (su sach)) ly hang xa hoi. ((hieu vien) OR (hieu viec)) cac luc va hanh dai cua te*.