Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
cong toan » cong tan, cong hoan, cong tuan
doanh hoa » doanh khoa, doanh hoan, danh hoa
thu sach » thuat sach, thuoc sach, thu hoach
nhan van » nhan dan, nhan va, phan van
tu sach » su sach, te sach, tu cach
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.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) hoc tap, nghien cua cong toan doanh hoa hoc xa hoi va nhan van~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) hoc tap, nghien cua cong toan doanh hoa hoc xa hoi va nhan van*.