Perhaps you should try some spelling variations:
cong thuong » hang thuong
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
trinh quan » trinh luat, trinh han
thuong dam » thuong mai, huong dan, truong dai
dam thanh » dao thanh, nam thanh, am thanh
thanh cao » thanh ca, thanh cac, thanh thao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu sang) or (chieu sach)) - hanh ((trinh quan) OR (tinh quang)) cong thuong dam thanh cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (chieu sach)) - hanh ((trinh quan) OR (tinh quang)) cong thuong dam thanh cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sang) or (chieu sach)) - hanh ((trinh quan) OR (tinh quang)) cong thuong dam thanh cao*".