Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, ho chieu
hoc thieu » toc thieu
tang luan » dung luan
anh tang » anh bang, anh dang, anh nang
luan han » luan hoan, luan phan, luan van
han cong » phan cong, hang cong, hanh cong
cong tan » cong tac, cong san, cong thanh
tran cau » tran chau, toan cau, ran cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) or (((hoc thieu) OR (hoc hien)))) sach - anh tang luan han cong tan tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (((hoc thieu) OR (hoc hien)))) sach - anh tang luan han cong tan tran cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) or (((hoc thieu) OR (hoc hien)))) sach - anh tang luan han cong tan tran cau".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (((hoc thieu) OR (hoc hien)))) sach - anh tang luan han cong tan tran cau*.