Perhaps you should try some spelling variations:
thuong cong » thong cong, thuong con, thuong dong
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
nang quan » ban quan
cong dan » cong san, cong tan, huong dan
dan chat » van chat, dan chan, ban chat
chat cao » chat co, chat cho, chat bao

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu lang) or (hieu quang)) - anh ((nang suat) or (nang quan)) thuong cong dan chat cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (hieu quang)) - anh ((nang suat) OR (nang quan)) thuong cong dan chat cao.
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) or (hieu quang)) - anh ((nang suat) or (nang quan)) thuong cong dan chat cao*.