Perhaps you should try some spelling variations:
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, hang cong
trinh cua » trinh luat, trinh luan, trinh chat
hoi hieu » hoi phieu, hoi tieu, moi hieu
tinh cua » sinh cua, tinh chat, tranh cua
quan dau » quan cau, qua dau, quan dac
ho hieu » ho chieu, nho hieu, co hieu

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) or (hoi hieu)) lang - hanh ((tinh cua) OR (trinh cua)) nhung cong trinh quan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho hieu) OR (hoi hieu)) lang - hanh ((tinh cua) OR (trinh cua)) nhung cong trinh quan dau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho hieu) or (hoi hieu)) lang - hanh ((tinh cua) OR (trinh cua)) nhung cong trinh quan dau".
• Adding a wildcard symbol may retrieve word variants: ((ho hieu) or (hoi hieu)) lang - hanh ((tinh cua) OR (trinh cua)) nhung cong trinh quan dau*.