Perhaps you should try some spelling variations:
loai doanh » lai doanh, loai danh, toan doanh
doanh khoa » toan khoa
sach hoc » cach hoc, sach hoi, mach hoc
mot loai » moi loai, mot ngoai, so loai
khoa hoc » hoa hoc
van nhan » van thanh, danh nhan, van khanh
van phan » van phong, van thanh, luan phan
tu sach » thu sach, su sach, te sach
cuu mot » cua mot, cuu mo, huu mot
ma hoi » mai hoi, xa hoi, ma hoa

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 hoc tap, nghien cuu mot loai doanh khoa hoc ma hoi ((van nhan) OR (van phan)) van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach hoc tap, nghien cuu mot loai doanh khoa hoc ma hoi ((van nhan) OR (van phan)) van".
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu mot loai doanh khoa hoc ma hoi ((van nhan) OR (van phan)) van*.