Perhaps you should try some spelling variations:
thuat mach » thuat sach, thuat tach, thuyet mach
mach hoc » cach hoc, dich hoc, anh hoc
cuu vuot » cuu duoc
hoc toan » hoc tan, hop toan, hoa toan
khoa hoc » hoa hoc
hoi hoa » hoi khoa, hoc hoa, hoi hoc
hoa van » hoa dan, hoang van, hoa phan
van dau » van dao, phan dau
hoc xa » hoc ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat mach hoc tap, nghien ((cuu mo) or (cuu vuot)) hoc toan khoa hoc xa hoi hoa van dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat mach hoc tap, nghien ((cuu mo) OR (cuu vuot)) hoc toan khoa hoc xa hoi hoa van dau.
• Adding a wildcard symbol may retrieve word variants: thuat mach hoc tap, nghien ((cuu mo) or (cuu vuot)) hoc toan khoa hoc xa hoi hoa van dau*.