Perhaps you should try some spelling variations:
hang khoa » dung khoa
thu sach » thuat sach, thuoc sach, thu hoach
hoc hang » hoc hanh, hoc bang, hoc tang
khoa hoc » hoa hoc
nhan dan » phan dau, gian dan, nhan tai
tu sach » su sach, te sach, tu cach
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: ((tu sach) or (thu sach)) hoc tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) hoc tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) hoc tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan*.