Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu qua, diep quang
trung tuan » trung thanh, trung tam, tran tuan
hieu quan » hieu qua, lieu quan, thien quan
trung cap » truong cao, trung tam
thong van » trong van, thong va, thong quan
van than » van thanh, van thang, van tuan
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: ho ((hieu quang) OR (hieu quan)) - thanh ((trung tuan) or (trung cap)) thong thong van than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu quang) OR (hieu quan)) - thanh ((trung tuan) OR (trung cap)) thong thong van than cap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu quang) OR (hieu quan)) - thanh ((trung tuan) or (trung cap)) thong thong van than cap".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu quang) OR (hieu quan)) - thanh ((trung tuan) or (trung cap)) thong thong van than cap*.