Perhaps you should try some spelling variations:
khoi thuat » ki thuat, hoc thuat
thuat mach » thuat sach, thuat tach, thuyet mach
trung quan » truong quan, trong quan, trung tuan
dung cong » dung trong
tung qua » tuong quan, duong qua, thong qua
dung qua » duong qua, dung quan, dung cua
cong tac » cong ty
tac than » tac thanh, tam than, tac nhan
than cao » toan cao, thai cao, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: khoi thuat mach - thanh ((((tung qua) OR (dung qua))) or (trung quan)) dung cong tac than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: khoi thuat mach - thanh ((((tung qua) OR (dung qua))) OR (trung quan)) dung cong tac than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "khoi thuat mach - thanh ((((tung qua) OR (dung qua))) or (trung quan)) dung cong tac than cao".
• Adding a wildcard symbol may retrieve word variants: khoi thuat mach - thanh ((((tung qua) OR (dung qua))) or (trung quan)) dung cong tac than cao*.