Perhaps you should try some spelling variations:
nhung phuong » dung phuong, nhu phuong, truong phuong
phuong tinh » phuong trinh, phuong binh, khuong tinh
hanh trang » thanh trung, canh tranh, hanh trinh
hieu lang » chieu sang, hieu quang, nhieu tang
trang va » tran van, hang va
toan cau » toan tap, toan tai
toan cao » toan tap
toan ban » van ban
ho hieu » ho chieu, hoi hieu, nho hieu

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 hieu lang - hanh trang va nhung phuong tinh ((((toan cau) OR (toan cao))) OR (toan ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh trang va nhung phuong tinh ((((toan cau) OR (toan cao))) or (toan ban))~".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh trang va nhung phuong tinh ((((toan cau) OR (toan cao))) or (toan ban))*.