Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
thanh dung » thanh duong, thanh tung, thanh hung
hang cong » dang cong, hang nong, bang cong
sang than » cang thang, dang thanh, sang tao
so thiet » soc thiet, hoc thiet, hoa thiet
van than » van thanh, van thang, van tuan
va hang » van hang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: so thiet tach - thanh dung va hang cong ((van than) or (sang than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so thiet tach - thanh dung va hang cong ((van than) OR (sang than)) cau.
• Adding a wildcard symbol may retrieve word variants: so thiet tach - thanh dung va hang cong ((van than) or (sang than)) cau*.