Perhaps you should try some spelling variations:
doi trinh » doc trinh, doi tinh, dong trinh
trinh tin » trinh kinh, trinh toan, trinh tu
cong cong » cong dong, trong cong, dung cong
dinh cuu » dinh chi
tinh cua » trinh cua, sinh cua, tinh chat
cong san » cong tac
san phan » san pham, van phan, sat phan
phan cau » phan dau, phan cac, phan tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi trinh tin - nhanh ((dinh cuu) or (tinh cua)) cong cong san phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi trinh tin - nhanh ((dinh cuu) OR (tinh cua)) cong cong san phan cau*.