Perhaps you should try some spelling variations:
doanh hoan » doanh doanh, doanh khoa, doanh nhan
mach hoc » cach hoc, dich hoc, anh hoc
cuu long » cuu cong, cuu tong, cuu nang
so doanh » so danh, su doanh, hoa doanh
hoan hoc » hoa hoc, toan hoc, hoang hoa
nhan dan » gian dan, nhan tai
phan dau » phan tu, hang dau
su mach » su sach
long so » long soc, cong so, dong so
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: su mach hoc tap, nghien cuu long so doanh hoan hoc ma hoi va ((nhan dan) OR (phan dau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su mach hoc tap, nghien cuu long so doanh hoan hoc ma hoi va ((nhan dan) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien cuu long so doanh hoan hoc ma hoi va ((nhan dan) OR (phan dau))*.