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
hanh tang » hanh trang, anh tang, hanh mang
cua thong » cua thuong, cua khong, cua tong
tang cua » mang cua, hang cua, tang luan
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu lang) or (hieu quang)) - hanh tang cua thong cong ((van toan) or (van tuan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (hieu quang)) - hanh tang cua thong cong ((van toan) OR (van tuan)) ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) or (hieu quang)) - hanh tang cua thong cong ((van toan) or (van tuan)) ban*.