Perhaps you should try some spelling variations:
bien tinh » bi tinh, diep tinh, ban tinh
dung cong » dung trong
cong vang » cong lang, cong quang, cong ngang
thanh chu » thanh chau, thanh cha, thanh thu
yen tinh » tuyen tinh
tranh va » tranh van, trang va, trinh va
phan cau » phan dau, phan cac, phan tu
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((bien tinh) or (yen tinh)) - canh tranh va dung cong vang ((thanh chu) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((bien tinh) OR (yen tinh)) - canh tranh va dung cong vang ((thanh chu) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: hoc ((bien tinh) or (yen tinh)) - canh tranh va dung cong vang ((thanh chu) or (phan cau))*.