Perhaps you should try some spelling variations:
thanh tuong » thanh thuong, thanh tung, thanh huong
hieu quang » thieu quang, hieu quan, hieu qua
cong thong » cong thuong, cong trong, dong thong
hieu lang » chieu sang, nhieu tang, hieu van
tuong cua » truong cua, huong cua, thong cua
cong tang » cong thang, cong tan, cong lang
cua bang » chua bang, cua ban, cua dang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu lang) OR (hieu quang)) - thanh tuong cua bang ((cong tang) or (cong thong)) van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - thanh tuong cua bang ((cong tang) OR (cong thong)) van ban*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) OR (hieu quang)) - thanh tuong cua bang ((cong tang) or (cong thong)) van ban*".