Perhaps you should try some spelling variations:
khanh phuong » khanh phong, thanh phuong, khanh phung
phuong cham » phuong phap, phuong thao
chieu sang » chieu sach, chieu xanh, hieu lang
doi chieu » doc hieu, doi chi, mot chieu
dung cong » dung trong
dung dat » dung va, dung tai
ban cu » ban cua, ban cau, ban tu

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 - khanh phuong cham ((dung dat) or (dung cong)) van ban cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sang - khanh phuong cham ((dung dat) OR (dung cong)) van ban cu*.