Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
luan hang » luan nang, luan han, luan hung
hang cong » dang cong, hang nong, bang cong
ho chieu » hoc thieu, doi chieu, mot chieu
san toan » van toan, dan toan, manh toan
dan than » dan chan, ban than, van than

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((theo chieu) OR (ho chieu)) sach - hanh tang luan hang cong ((san toan) or (dan than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (ho chieu)) sach - hanh tang luan hang cong ((san toan) OR (dan than)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((theo chieu) OR (ho chieu)) sach - hanh tang luan hang cong ((san toan) or (dan than)) cau".
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) OR (ho chieu)) sach - hanh tang luan hang cong ((san toan) or (dan than)) cau*.