Perhaps you should try some spelling variations:
thanh phuong » thanh huong, thanh chuong, khanh phong
thieu sach » thien hach, hieu cach, theo sach
chieu sach » chinh sach, chiet tach, chieu sang
phuong thi » phung thi, huong thi, phong thi
hang cong » dang cong, hang nong, thanh cong
bang cong » dang cong, bang song, dung cong
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

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 (chieu sach)) - thanh phuong thi ((hang cong) or (bang cong)) dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (chieu sach)) - thanh phuong thi ((hang cong) OR (bang cong)) dan toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (chieu sach)) - thanh phuong thi ((hang cong) or (bang cong)) dan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) OR (chieu sach)) - thanh phuong thi ((hang cong) or (bang cong)) dan toan cao*.