Perhaps you should try some spelling variations:
hanh truong » hanh trong, anh truong, manh truong
chiet tach » chieu sach
truong cao » truong dai
hieu lang » chieu sang, hieu quang, nhieu tang
cao trong » cao truong, cay trong, tao trong
tap toan » tap doan, tap quan, bai toan
ty toan » ly toan, huy toan, tam toan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((chiet tach) or (hieu lang)) - hanh truong cao trong cong ((ty toan) or (tap toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chiet tach) OR (hieu lang)) - hanh truong cao trong cong ((ty toan) OR (tap toan)) cau.
• Adding a wildcard symbol may retrieve word variants: doi ((chiet tach) or (hieu lang)) - hanh truong cao trong cong ((ty toan) or (tap toan)) cau*.