Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
sach hoc » cach hoc, sach hoi, mach hoc
dan khoa » dang khoa, da khoa, san khoa
khoa hoc » hoa hoc
te sach » toc sach
cuu mon » cuu mo, cuu mot, cuu cong
mon hoa » mon hoc, dong hoa, cong hoa
va nhan » van nhan, ca nhan, va phan
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: te sach hoc tap, nghien cuu mon hoa dan khoa hoc xa hoi ((va nhan) or (van thanh)) van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach hoc tap, nghien cuu mon hoa dan khoa hoc xa hoi ((va nhan) OR (van thanh)) van.
• Adding a wildcard symbol may retrieve word variants: te sach hoc tap, nghien cuu mon hoa dan khoa hoc xa hoi ((va nhan) or (van thanh)) van*.