Perhaps you should try some spelling variations:
ngang thanh » nang thanh, nganh thanh, ngan thanh
chieu sang » chieu sach, chieu xanh, hieu lang
cong ngang » cong nhan, cong quang, cong lang
doi chieu » doc hieu, doi chi, ho chieu
cua dung » qua dung, cua rung, cua nhung
cua dang » cua cong, cua ban
cua dong » chua dong, cua cong, cua nong
thanh tu » hanh tu, nhanh tu, thanh tung

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 - nhanh quang ((((cua dung) or (cua dang))) or (cua dong)) cong ngang thanh tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sang - nhanh quang ((((cua dung) OR (cua dang))) OR (cua dong)) cong ngang thanh tu.
• Adding a wildcard symbol may retrieve word variants: doi chieu sang - nhanh quang ((((cua dung) or (cua dang))) or (cua dong)) cong ngang thanh tu*.