Perhaps you should try some spelling variations:
dong trinh » cong trinh, dong tinh, dong tranh
hanh doanh » hang doanh, chinh doanh, doanh doanh
doanh luan » doanh nhan
dong doanh » dung doanh, trong doanh, doanh doanh
doi trinh » doc trinh, doi tinh, doi trong
luan nang » luan van, van nang, luan san
cong doan » cong dan, cong hoan, cong san
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) OR (dong trinh)) tinh - hanh doanh luan nang ((cong doan) or (dong doanh)) phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi trinh) OR (dong trinh)) tinh - hanh doanh luan nang ((cong doan) OR (dong doanh)) phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi trinh) OR (dong trinh)) tinh - hanh doanh luan nang ((cong doan) or (dong doanh)) phan cau".
• Adding a wildcard symbol may retrieve word variants: ((doi trinh) OR (dong trinh)) tinh - hanh doanh luan nang ((cong doan) or (dong doanh)) phan cau*.