Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, nhieu tang, hieu van
doanh cua » doanh luan
manh cua » ban cua
cong van » cong vang, cong san, song van
van chat » cao chat
chat cau » chat cam, chat cao, chat va

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

• If you are trying to use Boolean operators, they must be ALL CAPS: moi ((hieu lang) OR (hieu quang)) - canh ((doanh cua) OR (manh cua)) thong cong van chat cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "moi ((hieu lang) OR (hieu quang)) - canh ((doanh cua) or (manh cua)) thong cong van chat cau~".
• Adding a wildcard symbol may retrieve word variants: moi ((hieu lang) OR (hieu quang)) - canh ((doanh cua) or (manh cua)) thong cong van chat cau*.