Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu quang » thieu quang, hieu quan, hieu qua
trung quan » truong quan, trong quan, trung tuan
quan dang » quang dang, quan lang, quan dong
dang cong » dung cong
cong bang » cuong bang, dong bang, hong bang
thanh bac » nhanh bac, thanh bai, thanh san
doc hieu » toc thieu, hoc thieu, hoc hien
hanh cac » hang cac, hanh cat, hanh cham

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu quang - thanh trung quan dang cong bang ((hanh cac) or (thanh bac))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu quang - thanh trung quan dang cong bang ((hanh cac) OR (thanh bac)).
• Adding a wildcard symbol may retrieve word variants: doc hieu quang - thanh trung quan dang cong bang ((hanh cac) or (thanh bac))*.