Perhaps you should try some spelling variations:
dinh quang » tinh quang, minh quang, dinh duong
hieu quan » hieu qua, lieu quan, thien quan
trinh han » trinh quan
tong cong » trong cong, cong cong, dung cong
trinh he » trinh hoa, trinh thi, trinh ky
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cap » khan cap, thanh lap, thanh cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thien ((dinh quang) or (hieu quan)) - hanh ((trinh he) or (trinh han)) tong cong tan than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien ((dinh quang) OR (hieu quan)) - hanh ((trinh he) OR (trinh han)) tong cong tan than cap.
• Adding a wildcard symbol may retrieve word variants: thien ((dinh quang) or (hieu quan)) - hanh ((trinh he) or (trinh han)) tong cong tan than cap*.