Perhaps you should try some spelling variations:
khien tinh » thien tinh, khien thich, bien tinh
hanh tranh » canh tranh, hanh trinh, hanh trang
hoc khien » hoc hien, hoc nghien, hoc thieu
dang cong » dung cong
manh toan » thanh toan, anh tuan, tinh toan
tranh va » tranh van, trang va, trinh va
van than » van thanh, van thang, van tuan
va dang » van dang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc khien tinh - hanh tranh va dang cong ((manh toan) or (van than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc khien tinh - hanh tranh va dang cong ((manh toan) OR (van than)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc khien tinh - hanh tranh va dang cong ((manh toan) or (van than)) cau*.