Perhaps you should try some spelling variations:
chau tinh » cuu tinh, cua tinh, cac tinh
tra tuan » tran tuan, tra quan, ta tuan
tri tuan » tri quan, tran tuan, tri tue
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap
ha tinh » va tinh, may tinh

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: o ((chau tinh) OR (ha tinh)) - thanh ((tra tuan) OR (tri tuan)) trong cong tac toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "o ((chau tinh) or (ha tinh)) - thanh ((tra tuan) OR (tri tuan)) trong cong tac toan cau~".
• Adding a wildcard symbol may retrieve word variants: o ((chau tinh) or (ha tinh)) - thanh ((tra tuan) OR (tri tuan)) trong cong tac toan cau*.