Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
doi chieu » doc hieu, doi chi, mot chieu
cong phan » cong nhan, cong khan, chong phap
dung cong » dung trong
dung dat » dung va, dung tai
van chat » cao chat
van van » van ban, tan van, san van

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chieu sang - thanh cong phan ((dung dat) or (dung cong)) van van chat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sang - thanh cong phan ((dung dat) OR (dung cong)) van van chat*.