Perhaps you should try some spelling variations:
trong chuan » thong chuan, trong chan, trong thuan
hanh trong » hanh trang, anh trong, hinh trong
chuan dung » chan dung, chuyen dung, chua dong
hieu lang » chieu sang, hieu quang, nhieu tang
dung cong » dung trong
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi ((hieu lang) or (hieu qua)) - hanh trong chuan dung cong dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi ((hieu lang) OR (hieu qua)) - hanh trong chuan dung cong dan than cao*.