Perhaps you should try some spelling variations:
cua duong » cua huong, qua duong, tuan duong
trong dan » trong dang, trong san, trong tan
hoc hieu » hoc thieu, hoc hien, hoc dieu
doc hieu » toc thieu, hoc thieu, hoc hien
cua dong » chua dong, cua cong, cua dang
dan phan » doan phan, dan chan, van phan
phan cau » phan dau, phan cac, phan tu

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 hieu) OR (doc hieu)) manh - canh tranh ((cua duong) OR (cua dong)) trong dan phan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc hieu) OR (doc hieu)) manh - canh tranh ((cua duong) or (cua dong)) trong dan phan cau~".
• Adding a wildcard symbol may retrieve word variants: ((hoc hieu) OR (doc hieu)) manh - canh tranh ((cua duong) or (cua dong)) trong dan phan cau*.