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
ban mach » ban sach, ranh mach, ban hanh
mach hoc » cach hoc, dich hoc, anh hoc
cuu cong » cua cong, thu cong, cac cong
cong hoc » dong hoc, cong hoa, cong coc
thuoc va » thuc va, thuoc ma, thuong va
nhan tai » van tai, toan tai
hang tai » hang va, dung tai
va hoi » xa hoi, va hoc, va hoa
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: ban mach hoc tap, nghien cuu cong hoc nganh khong thuoc va hoi ca ((nhan tai) or (hang tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ban mach hoc tap, nghien cuu cong hoc nganh khong thuoc va hoi ca ((nhan tai) OR (hang tai)).
• Adding a wildcard symbol may retrieve word variants: ban mach hoc tap, nghien cuu cong hoc nganh khong thuoc va hoi ca ((nhan tai) or (hang tai))*.