Perhaps you should try some spelling variations:
cong thuong » hang thuong
thanh trung » thanh tung
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
thuong van » thong van, truong van, thuong va
trung cua » truong cua, trung tuan, trung cap
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sang) or (chieu sach)) - thanh trung cua cong thuong van ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu sach)) - thanh trung cua cong thuong van ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu sach)) - thanh trung cua cong thuong van ((toan cau) or (toan cao))*.