Perhaps you should try some spelling variations:
khien tinh » thien tinh, khien thich, bien tinh
hanh tranh » canh tranh, hanh trinh, hanh trang
dung thang » hung thang, cung thang, dung thuong
hoc khien » hoc hien, hoc nghien, hoc thieu
tranh cua » doanh cua, manh cua
tong cong » cong cong, dung cong, dang cong
thang ban » hang ban, tang ban, thanh ban

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc khien tinh - hanh tranh cua ((tong cong) or (trong cong)) dung thang ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc khien tinh - hanh tranh cua ((tong cong) OR (trong cong)) dung thang ban.
• Adding a wildcard symbol may retrieve word variants: hoc khien tinh - hanh tranh cua ((tong cong) or (trong cong)) dung thang ban*.