Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
ho chieu » theo chieu, hoc thieu, mot chieu
tran van » luan van
cong tam » cong tac, cong tan, cong nam
tam than » ban than
than cau » toan cau, phan cau, than cap
lan van » luan van, lang van, tan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (doi chieu)) sach - hanh ((tran van) or (lan van)) trong cong tam than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - hanh ((tran van) OR (lan van)) trong cong tam than cau.
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doi chieu)) sach - hanh ((tran van) or (lan van)) trong cong tam than cau*.