Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hoc thieu » toc thieu, hoc hien
trung cua » truong cua, trung tuan, dung cua
trung cap » truong cao, trung tam
cong cong » cong dong, trong cong, dung cong
van toan » van tuan, van tan, van thanh
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: hoc thieu xanh - thanh ((trung cua) OR (trung cap)) cong cong ((van toan) OR (bai toan)) cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - thanh ((trung cua) OR (trung cap)) cong cong ((van toan) or (bai toan)) cao~".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - thanh ((trung cua) OR (trung cap)) cong cong ((van toan) or (bai toan)) cao*.