Perhaps you should try some spelling variations:
chiet tach » chieu sach
hoc chiet » hoc thiet, hoc nhiet, hoc hien
trung cap » truong cao, trung tam
trung lap » truong lam, truong lop, trung tam
dung cong » dung trong
dan than » dan chan, van than, dan toan
ban than » ban thanh, van thanh, ban hang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc chiet tach - hanh ((trung cap) or (trung lap)) dung cong ((dan than) OR (ban than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - hanh ((trung cap) OR (trung lap)) dung cong ((dan than) OR (ban than)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chiet tach - hanh ((trung cap) or (trung lap)) dung cong ((dan than) OR (ban than)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc chiet tach - hanh ((trung cap) or (trung lap)) dung cong ((dan than) OR (ban than)) cau*.