Perhaps you should try some spelling variations:
luan nhung » luan chung, luan hung, quan nhung
nhung cong » dung cong, thong cong, hang cong
doi chieu » doi chi, ho chieu, mot chieu
hanh tang » hanh trang, anh tang, hanh mang
tang luan » dung luan
van thang » van thanh, van khang, van hang
doc hieu » toc thieu, hoc thieu, hoc hien
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: ((doi chieu) OR (doc hieu)) sach - hanh tang luan nhung cong ((dan than) or (van thang)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) sach - hanh tang luan nhung cong ((dan than) OR (van thang)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doc hieu)) sach - hanh tang luan nhung cong ((dan than) or (van thang)) cau".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (doc hieu)) sach - hanh tang luan nhung cong ((dan than) or (van thang)) cau*.