Perhaps you should try some spelling variations:
thanh trung » thanh tung
cua trong » cua truong, cua trung, qua trong
theo cau » theo chu, theo cap, theo dau
cau sach » cao sach, hau sach, rau sach
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cau » 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: theo cau sach - ((thanh trung) or (canh tranh)) cua trong cong tap toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo cau sach - ((thanh trung) OR (canh tranh)) cua trong cong tap toan cau.
• Adding a wildcard symbol may retrieve word variants: theo cau sach - ((thanh trung) or (canh tranh)) cua trong cong tap toan cau*.