Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
doanh khoa » toan khoa
thu sach » tu sach, thuat sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
khoa hoc » hoa hoc
phan tan » phan van, phan tap, phan lan
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 hoc tap, nghien cua ((van hoc) or (van hoa)) doanh khoa hoc xa hoi va phan tan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach hoc tap, nghien cua ((van hoc) OR (van hoa)) doanh khoa hoc xa hoi va phan tan.
• Adding a wildcard symbol may retrieve word variants: thu sach hoc tap, nghien cua ((van hoc) or (van hoa)) doanh khoa hoc xa hoi va phan tan*.