Perhaps you should try some spelling variations:
nghien huu » nghien cuu, nguyen huu, nhiem huu
goc doanh » hoa doanh, von doanh, ngoc oanh
voi doanh » von doanh, tri doanh, hoa doanh
thu sach » tu sach, thuat sach, thuoc sach
sach toi » sach doi, sach hoi, sach moi
khoa hoc » hoa hoc
phan van » pham van, thanh van, luan van
toi tap » toi gap, toan tap, tong tap
huu mot » cuu mot, huy mot, hieu mot
va phan » van phan, va phat, va phap
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: thu sach toi tap, nghien huu mot ((goc doanh) or (voi doanh)) khoa hoc xa hoi va phan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach toi tap, nghien huu mot ((goc doanh) OR (voi doanh)) khoa hoc xa hoi va phan van.
• Adding a wildcard symbol may retrieve word variants: thu sach toi tap, nghien huu mot ((goc doanh) or (voi doanh)) khoa hoc xa hoi va phan van*.