Perhaps you should try some spelling variations:
doanh doanh » toan doanh, doanh hoan, doanh thanh
thiet tach » chiet tach, thien hach, thuat tach
doanh luan » doanh nhan
duong cong » luong cong, duong trong, trong cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
dung cong » dung trong
san ban » sang ban, van ban, can 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 thiet tach - doanh doanh luan ((duong cong) or (dung cong)) thanh san ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - doanh doanh luan ((duong cong) OR (dung cong)) thanh san ban.
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - doanh doanh luan ((duong cong) or (dung cong)) thanh san ban*.