Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
chieu xanh » chieu sach, chieu sang, chieu tinh
nhung cong » dung cong, thong cong, hang cong
cua nhung » va nhung
anh tang » anh bang, anh nang, anh sang
anh dang » anh dong, anh dung, anh bang
tap toan » tap quan, bai toan
tap doan » tap quan

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 - ((anh tang) or (anh dang)) cua nhung cong ((tap toan) OR (tap doan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu xanh - ((anh tang) OR (anh dang)) cua nhung cong ((tap toan) OR (tap doan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu xanh - ((anh tang) or (anh dang)) cua nhung cong ((tap toan) OR (tap doan)) cao".
• Adding a wildcard symbol may retrieve word variants: theo chieu xanh - ((anh tang) or (anh dang)) cua nhung cong ((tap toan) OR (tap doan)) cao*.