Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
truong cao » truong dai
truong va » truong dai, truong dao, luong va
hang nong » thang long, han tong
tac toan » tam toan, hach toan, tich toan
tap toan » tap doan, tap quan, bai toan
ho hieu » ho chieu, hoi hieu, nho hieu

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 - thanh ((truong va) OR (truong cao)) hang nong ((tac toan) or (tap toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu quang - thanh ((truong va) OR (truong cao)) hang nong ((tac toan) OR (tap toan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu quang - thanh ((truong va) OR (truong cao)) hang nong ((tac toan) or (tap toan)) tap".
• Adding a wildcard symbol may retrieve word variants: ho hieu quang - thanh ((truong va) OR (truong cao)) hang nong ((tac toan) or (tap toan)) tap*.