Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu manh » chieu xanh, hieu nganh, dieu hanh
hieu lang » chieu sang, hieu quang, nhieu tang
dung cong » dung trong
trung va » truong va, trang va, trung ha
cong van » cong vang, cong san, song van
tuan cau » toan cau, tuan cu, thuan cam
quan cau » quang cao, toan cau, quan ha
va dung » van dung, va duong, vat dung

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 manh) OR (hieu lang)) - thanh trung va dung cong van ((tuan cau) OR (quan cau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu manh) or (hieu lang)) - thanh trung va dung cong van ((tuan cau) OR (quan cau))~".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu manh) or (hieu lang)) - thanh trung va dung cong van ((tuan cau) OR (quan cau))*.