Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
huong ban » huong dan, huong ben, huong lan
lap luan » phap luan, ly luan, luc luan
ban than » ban thanh, van thanh, ban hang
than cau » toan cau, phan cau, than cap

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)) - thanh trung ((lap ban) OR (lap luan)) huong ban than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - thanh trung ((lap ban) OR (lap luan)) huong ban than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (thien hach)) - thanh trung ((lap ban) OR (lap luan)) huong ban than cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - thanh trung ((lap ban) OR (lap luan)) huong ban than cau*.