Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
van thanh » ban thanh, van tuan
danh nhan » doanh nhan, thanh nhan, benh nhan
toc sach » hoc sach, doc sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
dan hoat » dan hoc, danh hoa, van hoan
hoat hoc » hoa hoc, hoat ho, khoa hoc
cua van » cua ban, cua vat, cua dan
hoc xa » hoc ma
hoa » khoa
hoat » khoat

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach hoc tap, nghien cua van hoa dan hoat hoc xa hoi ((van thanh) or (danh nhan)) tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach hoc tap, nghien cua van hoa dan hoat hoc xa hoi ((van thanh) OR (danh nhan)) tai.
• Adding a wildcard symbol may retrieve word variants: toc sach hoc tap, nghien cua van hoa dan hoat hoc xa hoi ((van thanh) or (danh nhan)) tai*.