Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
canh manh » lanh manh, canh tranh, cach mang
cua thong » cua thuong, cua khong, cua tong
cong vang » cong lang, cong quang, cong ngang
thanh tai » thanh hai, thanh toan, doanh tai
manh cua » doanh cua, ban cua
cong van » cong san, song van, cong tan

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)) - canh manh cua thong ((cong van) or (cong vang)) thanh tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu sach)) - canh manh cua thong ((cong van) OR (cong vang)) thanh tai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) OR (chieu sach)) - canh manh cua thong ((cong van) or (cong vang)) thanh tai".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) OR (chieu sach)) - canh manh cua thong ((cong van) or (cong vang)) thanh tai*.