Perhaps you should try some spelling variations:
sach hoc » cach hoc, sach hoi, sach duoc
mach hoc » cach hoc, dich hoc, anh hoc
van khoa » van hoa, von khoa, san khoa
khoa hoc » hoa hoc
nhan tai » hang tai, van tai, toan tai
hoc van » hoc dan, hoc va, hoc vat
va nhan » van nhan, ca nhan, va phan
mo hoc » mon hoc, co hoc
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 ((sach hoc) or (mach hoc)) tap, nghien cuu mo hoc van khoa hoc xa hoi va nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach hoc) OR (mach hoc)) tap, nghien cuu mo hoc van khoa hoc xa hoi va nhan tai.
• Adding a wildcard symbol may retrieve word variants: su ((sach hoc) or (mach hoc)) tap, nghien cuu mo hoc van khoa hoc xa hoi va nhan tai*.