Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
chieu xanh » chieu sach, chieu sang, chieu tinh
dung cong » dung trong
tung cao » truong cao, trung cap, quang cao
nung cao » nang cao, nhung cau, quang cao
tac toan » tap toan, hach toan, tich toan
tam toan » tap toan, tam than, pham toan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo chieu xanh - thanh ((tung cao) or (nung cao)) dung cong ((tac toan) OR (tam toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu xanh - thanh ((tung cao) OR (nung cao)) dung cong ((tac toan) OR (tam toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu xanh - thanh ((tung cao) or (nung cao)) dung cong ((tac toan) OR (tam toan)) cao".
• Adding a wildcard symbol may retrieve word variants: theo chieu xanh - thanh ((tung cao) or (nung cao)) dung cong ((tac toan) OR (tam toan)) cao*.