Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
doi chieu » doc hieu, doi chi, ho chieu
chieu qua » hieu qua, khien qua, hieu cua
tinh cua » trinh cua, sinh cua, tinh chat
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tap » toan ban
sinh va » sinh vat, tinh va, dinh van

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: doi chieu qua - thanh ((((tinh cua) OR (sinh va))) OR (trinh luat)) thong cong dan toan tap~.
• Adding a wildcard symbol may retrieve word variants: doi chieu qua - thanh ((((tinh cua) or (sinh va))) or (trinh luat)) thong cong dan toan tap*.