Perhaps you should try some spelling variations:
tren thanh » trien thanh, tran thanh, tien thanh
hanh tranh » hanh trinh, hanh trang, lanh tranh
nhung cong » dung cong, thong cong, hang cong
hoc tren » moc tren, hoc truyen, thuoc tren
cong tan » cong tac, cong san, cong thanh
tran cau » tran chau, toan cau, ran cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc tren thanh - ((hanh tranh) or (canh tranh)) va nhung cong tan tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc tren thanh - ((hanh tranh) OR (canh tranh)) va nhung cong tan tran cau.
• Adding a wildcard symbol may retrieve word variants: hoc tren thanh - ((hanh tranh) or (canh tranh)) va nhung cong tan tran cau*.