Perhaps you should try some spelling variations:
chieu tach » chiet tach, chieu sach, chiu trach
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, hang cong
trinh cua » tinh cua, trinh luat, trinh luan
ho chieu » theo chieu, hoc thieu, doi chieu
dan toan » van toan, manh toan, xuan toan
dan than » dan chan, ban than, van than

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho chieu tach - hanh ((trinh cua) OR (trinh quan)) nhung cong ((dan toan) OR (dan than)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu tach - hanh ((trinh cua) OR (trinh quan)) nhung cong ((dan toan) or (dan than)) cau~".
• Adding a wildcard symbol may retrieve word variants: ho chieu tach - hanh ((trinh cua) OR (trinh quan)) nhung cong ((dan toan) or (dan than)) cau*.