Perhaps you should try some spelling variations:
nganh khong » nganh cong, nhanh chong, nganh nong
khong hoc » khung hoc, thong hoc, khong thuoc
sach hoc » cach hoc, sach hoi, mach hoc
cong coc » cong cuoc, cong cac, cong co
cong tac » cong ty
nhan dan » phan dau, gian dan, nhan tai
tu sach » thu sach, su sach, te sach
hoc lai » hoc dai, hoc bai, hoc lam
lai hoi » dai hoi, lai hoa, lai roi
va nhan » van nhan, ca nhan, va phan

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 hoc tap, nghien cuu ((cong coc) or (cong tac)) nganh khong hoc lai hoi va nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoc tap, nghien cuu ((cong coc) OR (cong tac)) nganh khong hoc lai hoi va nhan dan.
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu ((cong coc) or (cong tac)) nganh khong hoc lai hoi va nhan dan*.