Perhaps you should try some spelling variations:
truong cong » trong cong, truong dong, truong long
chieu xanh » chieu sach, chieu sang, chieu tinh
cua truong » cua trung, xuan truong, cac truong
anh quang » anh xquang, anh quan, nhanh quang
ho chieu » theo chieu, hoc thieu, doi chieu
anh bang » anh hoang, tinh bang, anh dong
dan toan » van toan, dan than, manh toan
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: ho chieu xanh - ((anh bang) OR (anh quang)) cua truong cong ((dan toan) OR (bai toan)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu xanh - ((anh bang) OR (anh quang)) cua truong cong ((dan toan) or (bai toan)) cau~".
• Adding a wildcard symbol may retrieve word variants: ho chieu xanh - ((anh bang) OR (anh quang)) cua truong cong ((dan toan) or (bai toan)) cau*.