Perhaps you should try some spelling variations:
nganh khong » nganh cong, nhanh chong, nganh nong
khong thuoc » khang thuoc, hong phuoc, dong thuoc
hoc nganh » hoc nhanh
nhan dann » nhan dang, phan dang, nhac dan
sach hoc » cach hoc, sach hoi, mach hoc
thuoc ma » hoc ma, duoc ma
nhan dan » phan dau, gian dan, nhan tai
so sach » so sanh, bo sach, co sach
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach hoc tap, nghien cuu mon hoc nganh khong thuoc ma hoi va ((nhan dann) or (nhan dan))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach hoc tap, nghien cuu mon hoc nganh khong thuoc ma hoi va ((nhan dann) OR (nhan dan)).
• Adding a wildcard symbol may retrieve word variants: so sach hoc tap, nghien cuu mon hoc nganh khong thuoc ma hoi va ((nhan dann) or (nhan dan))*.