Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
doanh khoa » toan khoa
nganh hoa » thanh hoa, khanh hoa, danh hoa
sach hoc » cach hoc, sach hoi, mach hoc
cong coc » cong cuoc, cong cac, cong co
nhan dan » phan dau, gian dan, nhan tai
su sach » so sach, vu sach
hoc xa » hoc ma
hoi ca » hoi cua, hoi cac, hoi cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach hoc tap, nghien cua cong coc ((doanh khoa) or (nganh hoa)) hoc xa hoi ca nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoc tap, nghien cua cong coc ((doanh khoa) OR (nganh hoa)) hoc xa hoi ca nhan dan.
• Adding a wildcard symbol may retrieve word variants: su sach hoc tap, nghien cua cong coc ((doanh khoa) or (nganh hoa)) hoc xa hoi ca nhan dan*.