Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
trung gay » trung tam, trung cap, trung ha
trong gay » trong cay, trong giao, trong giai
dung cong » dung trong
thanh cac » hanh cac, thanh bac, thanh ca
doc hieu » toc thieu, hoc thieu, hoc hien
cong dan » cong san, cong tan, huong dan
than cap » khan cap, thanh lap, than cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu lang - thanh ((trung gay) or (trong gay)) dung cong dan ((than cap) OR (thanh cac))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu lang - thanh ((trung gay) OR (trong gay)) dung cong dan ((than cap) OR (thanh cac)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu lang - thanh ((trung gay) or (trong gay)) dung cong dan ((than cap) OR (thanh cac))".
• Adding a wildcard symbol may retrieve word variants: doc hieu lang - thanh ((trung gay) or (trong gay)) dung cong dan ((than cap) OR (thanh cac))*.