Perhaps you should try some spelling variations:
mach hoc » cach hoc, dich hoc, anh hoc
dong hoc » dong luc
pho khoa » phu khoa, pha khoa, tho khoa
khoa hoc » hoa hoc
gian dan » gian lang
su mach » su sach
va gian » va gianh, van gian, va giai
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: su mach hoc tap, nghien cuu ((dong hoc) or (dong co)) pho khoa hoc xa hoi va gian dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su mach hoc tap, nghien cuu ((dong hoc) OR (dong co)) pho khoa hoc xa hoi va gian dan.
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien cuu ((dong hoc) or (dong co)) pho khoa hoc xa hoi va gian dan*.