Perhaps you should try some spelling variations:
khoa nganh » khoi nganh, hoc nganh
nganh nong » nganh cong
nong thoi » nong thon, nong thi, trong thoi
mach hoc » cach hoc, dich hoc, anh hoc
han khoa » hang khoa, nhan khoa, san khoa
su mach » su sach
cuu han » cuu nhan, cuu hoan, cuu phan
thoi xa » thoi xua, thi xa, thoi va
han va » hanh va, nhan va, ban va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su mach hoc tap, nghien cuu han khoa nganh nong thoi xa hoi va ((han va) or (hang va))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su mach hoc tap, nghien cuu han khoa nganh nong thoi xa hoi va ((han va) OR (hang va)).
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien cuu han khoa nganh nong thoi xa hoi va ((han va) or (hang va))*.