Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
tran manh » tran minh, tran thanh, tran van
van dung » van dong, tin dung
cong dan » cong san, cong tan, huong dan
dan tran » dang tran, tan tran, dan than

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - thanh trung ((van dung) OR (xay dung)) cong dan tran manh~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) OR (hieu quang)) - thanh trung ((van dung) or (xay dung)) cong dan tran manh~".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) OR (hieu quang)) - thanh trung ((van dung) or (xay dung)) cong dan tran manh*.