Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, hang cong
hoc chieu » hoc thieu, ho chieu, hoc hien
trinh cua » tinh cua, trinh luat, trinh luan
tap quan » tac quan, hai 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: hoc chieu xanh - hanh ((trinh cua) OR (trinh quan)) nhung cong ((tap quan) OR (bai toan)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chieu xanh - hanh ((trinh cua) OR (trinh quan)) nhung cong ((tap quan) or (bai toan)) cau~".
• Adding a wildcard symbol may retrieve word variants: hoc chieu xanh - hanh ((trinh cua) OR (trinh quan)) nhung cong ((tap quan) or (bai toan)) cau*.