Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
nhung cong » dung cong, thong cong, hang cong
tuong cua » truong cua, huong cua, thong cua
hach toan » thanh toan, manh toan
ho chieu » theo chieu, hoc thieu, doi chieu
tung cua » trung cua, dung cua, tang cua
tac toan » tap toan, tam toan, tich toan

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: ho chieu xanh - thanh ((tung cua) OR (tuong cua)) nhung cong ((tac toan) OR (hach toan)) tap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu xanh - thanh ((tung cua) OR (tuong cua)) nhung cong ((tac toan) or (hach toan)) tap~".
• Adding a wildcard symbol may retrieve word variants: ho chieu xanh - thanh ((tung cua) OR (tuong cua)) nhung cong ((tac toan) or (hach toan)) tap*.