Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu qua, diep quang
thanh tung » thanh cong
dung huong » dung thuong, dung phuong, dong huong
hieu quan » hieu qua, lieu quan, thien quan
chan dung » van dung, dan dung
huong ban » huong dan, huong ben, huong lan
ban than » ban thanh, van thanh, ban hang
than cap » khan cap, thanh lap, thanh cac

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 quang) OR (hieu quan)) - ((thanh trung) or (thanh tung)) chan dung huong ban than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu quang) OR (hieu quan)) - ((thanh trung) OR (thanh tung)) chan dung huong ban than cap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu quang) OR (hieu quan)) - ((thanh trung) or (thanh tung)) chan dung huong ban than cap".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu quang) OR (hieu quan)) - ((thanh trung) or (thanh tung)) chan dung huong ban than cap*.