Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hieu quang » thieu quang, hieu qua, diep quang
nhung cong » dung cong, thong cong, hang cong
hieu quan » hieu qua, lieu quan, thien quan
trinh cua » tinh cua, trinh luat, trinh quan
cua nhung » va nhung
toan phan » thanh phan, hoa phan, luan phan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu quang) or (hieu quan)) - hanh trinh cua nhung cong ((toan phan) OR (toan ban)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu quang) OR (hieu quan)) - hanh trinh cua nhung cong ((toan phan) OR (toan ban)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu quang) or (hieu quan)) - hanh trinh cua nhung cong ((toan phan) OR (toan ban)) cau".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu quang) or (hieu quan)) - hanh trinh cua nhung cong ((toan phan) OR (toan ban)) cau*.