Perhaps you should try some spelling variations:
tong duong » tuong duong, thong duong, dong duong
hanh tranh » canh tranh, hanh trinh, hanh trang
duong manh » duong van
tranh cua » doanh cua, manh cua
theo chu » theo chieu, cho chu, chao chu
chu sang » chu bang, thu sang, chieu sang
cua tong » cua cong, cua dong, cua nong
toan tai » doanh tai, toan ban, toan cao
toan tap » toan ban

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: theo chu sang - hanh tranh cua tong duong manh ((toan tai) OR (toan tap))~.
• Adding a wildcard symbol may retrieve word variants: theo chu sang - hanh tranh cua tong duong manh ((toan tai) or (toan tap))*.