Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, nhung don
trinh phan » trinh han, trinh quan, thanh phan
hieu manh » chieu xanh, hieu nganh, hien hanh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
hang cong » dang cong, hang nong, bang cong
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: doc ((hieu manh) or (dieu hanh)) - hanh tinh quang ((nhung cong) OR (hang cong)) trinh phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (dieu hanh)) - hanh tinh quang ((nhung cong) OR (hang cong)) trinh phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu manh) or (dieu hanh)) - hanh tinh quang ((nhung cong) OR (hang cong)) trinh phan cau".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu manh) or (dieu hanh)) - hanh tinh quang ((nhung cong) OR (hang cong)) trinh phan cau*.