Perhaps you should try some spelling variations:
hieu tinh » chieu tinh, lieu tinh, kieu tinh
canh manh » lanh manh, canh tranh, cach mang
manh toan » thanh toan, anh tuan, tinh toan
doc hieu » toc thieu, hoc thieu, hoc hien
manh cua » doanh cua, ban cua
ban cong » bang cong, van cong, phan cong
van tan » van tuan, van ban, van tai

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: doc hieu tinh - canh manh cua ban cong ((((xuan toan) OR (van tan))) OR (manh toan)) cau~.
• Adding a wildcard symbol may retrieve word variants: doc hieu tinh - canh manh cua ban cong ((((xuan toan) or (van tan))) or (manh toan)) cau*.