Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
tieu tinh » trieu tinh, tieu trinh, lieu tinh
cong manh » cong danh, duong manh, cong thanh
manh toan » thanh toan, anh tuan, tinh toan
trang va » hang va
tran van » luan van
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu tinh - hanh ((trang va) OR (tran van)) nhung cong manh toan cau~.
• Adding a wildcard symbol may retrieve word variants: theo tieu tinh - hanh ((trang va) or (tran van)) nhung cong manh toan cau*.