Perhaps you should try some spelling variations:
nhung cong » thong cong, hang cong, nhung don
hanh trung » thanh trung, hanh trang, manh trung
hieu lang » chieu sang, hieu quang, nhieu tang
trung cap » truong cao, trung tam
dung cong » dung trong
dan toan » van toan, dan than, manh toan
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: hoc ((dieu hanh) or (hieu lang)) - hanh trung cap ((nhung cong) or (dung cong)) dan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((dieu hanh) OR (hieu lang)) - hanh trung cap ((nhung cong) OR (dung cong)) dan toan ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((dieu hanh) or (hieu lang)) - hanh trung cap ((nhung cong) or (dung cong)) dan toan ban*.