Perhaps you should try some spelling variations:
hang khoa » dung khoa
sach hoc » cach hoc, mach hoc, sach duoc
sach hoi » sach doi, sach moi, cach thoi
hoc hang » hoc hanh, hoc bang, hoc tang
khoa hoc » hoa hoc
nhan dan » phan dau, gian dan, nhan tai
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: bo ((sach hoc) OR (sach hoi)) tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "bo ((sach hoc) OR (sach hoi)) tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan".
• Adding a wildcard symbol may retrieve word variants: bo ((sach hoc) OR (sach hoi)) tap, nghien cuu mo hoc hang khoa hoc xa hoi va nhan dan*.