Perhaps you should try some spelling variations:
khong thuoc » khang thuoc, hong phuoc, dong thuoc
thuat sach » thuat lanh, thuat san
nhan khong » nhan thong, nhanh chong, nganh khong
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
dong hoc » dong co, dong luc
hoc nhan » hoc nhanh, nhoc nhan, hoc phan
thuoc ma » hoc ma, duoc ma
nhan tao » nhan tai, nhan dan
nhan va » nhan tai, nhan dan, phan van
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: thuat sach hoc tap, nghien cuu dong hoc nhan khong thuoc ma hoi va ((nhan va) or (nhan tao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach hoc tap, nghien cuu dong hoc nhan khong thuoc ma hoi va ((nhan va) OR (nhan tao)).
• Adding a wildcard symbol may retrieve word variants: thuat sach hoc tap, nghien cuu dong hoc nhan khong thuoc ma hoi va ((nhan va) or (nhan tao))*.