Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
cong cong » cong dong, trong cong, dung cong
ho chieu » hoc thieu, doi chieu, mot chieu
anh nang » ganh nang, anh bang, anh dang
nang cua » mang cua, hang cua, nang dua
tap toan » tap doan, tap quan
bai toan » bai tap

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

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