Perhaps you should try some spelling variations:
chap thuong » chan thuong, phan thuong, pham thuong
thanh trung » thanh tung
thuong cong » thong cong, thuong con, thuong dong
chieu sang » chieu sach, chieu xanh, nhieu tang
trung chap » trung cap, trung ha, tranh chap
hieu lang » hieu quang, nhieu tang, hieu van
cong tap » cuong tap, cong tac, cong tan
toan tai » toan tap, doanh tai, toan ban
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: doc ((chieu sang) OR (hieu lang)) - thanh trung chap thuong cong tap ((toan tai) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((chieu sang) OR (hieu lang)) - thanh trung chap thuong cong tap ((toan tai) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((chieu sang) OR (hieu lang)) - thanh trung chap thuong cong tap ((toan tai) or (toan cao))".
• Adding a wildcard symbol may retrieve word variants: doc ((chieu sang) OR (hieu lang)) - thanh trung chap thuong cong tap ((toan tai) or (toan cao))*.