Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
phuong lan » phuong la, thuong lan, phuong linh
hien xanh » hien hanh, hien nhanh, hien khanh
lan toan » van toan, dan toan, lap toan
toan cau » toan cao, toan ban, toan tap
cua nhu » cua nhua, cua chu, cua khu
cua nha » cua nhan, cua ngan

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 ((hien xanh) OR (chieu xanh)) - nhanh quang ((cua nhu) OR (cua nha)) phuong lan toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) or (chieu xanh)) - nhanh quang ((cua nhu) OR (cua nha)) phuong lan toan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) or (chieu xanh)) - nhanh quang ((cua nhu) OR (cua nha)) phuong lan toan cau*.