Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
ban thanh » ban hanh, ban hang
mach hoc » cach hoc, dich hoc, anh hoc
cong hoc » dong hoc, cong hoa, cong coc
su mach » su sach
hoi ban » hoi dan, hoi bai, doi ban
hoc xa » hoc ma
toan » tran

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 thu cong hoc ((doanh khoa) OR (toan khoa)) hoc xa hoi ban thanh san~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su mach hoc tap, nghien thu cong hoc ((doanh khoa) OR (toan khoa)) hoc xa hoi ban thanh san".
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien thu cong hoc ((doanh khoa) OR (toan khoa)) hoc xa hoi ban thanh san*.