Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sach » chinh sach, chiet tach, chieu sang
trung hieu » thuong hieu, trung kien, trong hiep
thong cong » trong cong, thong thong, phong chong
tong cong » trong cong, cong cong, dung cong
tap toan » tap doan, tap quan, bai toan
toan ban » van ban
tinh » trinh, dinh, minh

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((trieu tinh) or (chieu sach)) - thanh trung hieu ((thong cong) OR (tong cong)) tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((trieu tinh) OR (chieu sach)) - thanh trung hieu ((thong cong) OR (tong cong)) tap toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((trieu tinh) or (chieu sach)) - thanh trung hieu ((thong cong) OR (tong cong)) tap toan ban".
• Adding a wildcard symbol may retrieve word variants: ho ((trieu tinh) or (chieu sach)) - thanh trung hieu ((thong cong) OR (tong cong)) tap toan ban*.