Perhaps you should try some spelling variations:
thien chanh » thien thanh, thien chinh, hien hanh
hanh tranh » canh tranh, hanh trinh, hanh trang
nhung cong » thong cong, hang cong, nhung don
tranh cua » doanh cua, manh cua
dung cong » dung trong
tien anh » tieng anh, tien manh, dien anh
van toan » van tuan, van tan, van thanh
toan ban » van 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 ((tien anh) or (thien chanh)) - hanh tranh cua ((nhung cong) OR (dung cong)) van toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((tien anh) OR (thien chanh)) - hanh tranh cua ((nhung cong) OR (dung cong)) van toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((tien anh) or (thien chanh)) - hanh tranh cua ((nhung cong) OR (dung cong)) van toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((tien anh) or (thien chanh)) - hanh tranh cua ((nhung cong) OR (dung cong)) van toan ban*.