Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
hanh tran » hanh trang, thanh tran, hanh tram
dung cong » dung trong
ho chieu » theo chieu, hoc thieu, mot chieu
tran van » luan van
van dung » van dong, xay dung, tin dung
tan toan » tan tran, tap toan, van toan

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 dung cong ((tan toan) or (von tai)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - hanh tran van dung cong ((tan toan) OR (von tai)) cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (doi chieu)) sach - hanh tran van dung cong ((tan toan) or (von tai)) cau*".