Perhaps you should try some spelling variations:
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, hang cong
trinh cua » tinh cua, trinh luat, trinh luan
theo chu » theo chieu, cho chu, chao chu
chu sach » cau sach, thu sach, chieu sach
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.

• Performing a fuzzy search may retrieve terms with similar spellings: theo chu sach - hanh ((trinh cua) or (trinh quan)) nhung cong ((dan toan) or (dan than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chu sach - hanh ((trinh cua) OR (trinh quan)) nhung cong ((dan toan) OR (dan than)) cau.
• Adding a wildcard symbol may retrieve word variants: theo chu sach - hanh ((trinh cua) or (trinh quan)) nhung cong ((dan toan) or (dan than)) cau*.