Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
dung thanh » duong thanh, dong thanh, dang thanh
hoc thiet » hoc thieu, hoc thuyet, hoc hien
tuong dan » tung dan, xuong dan, truong dai
cong dung » cuong dung, cong dong, cong luong
thanh lap » thanh san, phan lap, thanh hai
ho thiet » hoa thiet, so thiet, hoc thieu

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) or (ho thiet)) tach - thanh ((tuong dan) OR (huong dan)) nhung cong dung thanh lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (ho thiet)) tach - thanh ((tuong dan) OR (huong dan)) nhung cong dung thanh lap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thiet) or (ho thiet)) tach - thanh ((tuong dan) OR (huong dan)) nhung cong dung thanh lap".
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (ho thiet)) tach - thanh ((tuong dan) OR (huong dan)) nhung cong dung thanh lap*.