Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
thuat mach » thuat sach, thuat tach, thuyet mach
tang luan » dung luan
luan hang » luan nang, luan han, luan hung
hang cong » dang cong, hang nong, bang cong
anh tang » anh bang, anh dang, anh nang
dan than » dan chan, ban than, van than
van tuan » van quan, van ban, anh tuan

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) or (thuat mach)) - anh tang luan hang cong ((dan than) or (van tuan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thiet tach) OR (thuat mach)) - anh tang luan hang cong ((dan than) OR (van tuan)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thiet tach) or (thuat mach)) - anh tang luan hang cong ((dan than) or (van tuan)) cau*.