Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
thanh tung » thanh cong
tran dung » tran dang, tran hung, trung dung
cong dang » cong dong, cong dan, cong dung
so thiet » soc thiet, hoc thiet, hoa thiet
dang van » hoang van, hang va
van lap » van lam, dan lap, van dap

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 tung ((tran dung) or (tran quang)) cong dang van lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so thiet tach - thanh tung ((tran dung) OR (tran quang)) cong dang van lap.
• Adding a wildcard symbol may retrieve word variants: so thiet tach - thanh tung ((tran dung) or (tran quang)) cong dang van lap*.