Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
nganh khoa » nganh hoa, nganh khong, doanh khoa
hoc nganh » hoc nhanh
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
khoa hoc » hoa hoc
nhan tai » hang tai, van tai, toan tai
tu sach » thu sach, su sach, te sach
so sach » so sanh, bo sach, co sach
cu nhan » ca nhan
hoc xa » hoc ma
hoi cu » hoi chu, hoi cua, 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: ((tu sach) or (so sach)) hoc tap, nghien cac cong hoc nganh khoa hoc xa hoi cu nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (so sach)) hoc tap, nghien cac cong hoc nganh khoa hoc xa hoi cu nhan tai.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) hoc tap, nghien cac cong hoc nganh khoa hoc xa hoi cu nhan tai*.