Perhaps you should try some spelling variations:
dong phuong » duong phuong, dung phuong, dong huong
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
hanh tran » hanh trang, thanh tran, hanh tram
tran van » luan van
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: hoc ((thieu sach) or (thien hach)) - hanh tran van dong phuong ((dan toan) OR (dan than)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - hanh tran van dong phuong ((dan toan) OR (dan than)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (thien hach)) - hanh tran van dong phuong ((dan toan) OR (dan than)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - hanh tran van dong phuong ((dan toan) OR (dan than)) cao*.