Perhaps you should try some spelling variations:
hoc doanh » hoa doanh, hoc danh, hoc dan
doanh hoa » doanh khoa, doanh hoan, danh hoa
sach hoc » cach hoc, sach hoi, mach hoc
cuu tong » cuu cong, cuu tinh, huu tung
tong hoc » tuong hoc, thong hoc, trong hoc
nhan dan » gian dan, nhan tai
phan dau » phan tu, hang dau
so sach » so sanh, bo sach, co sach
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: so sach hoc tap, nghien cuu tong hoc doanh hoa hoc ma hoi va ((nhan dan) OR (phan dau))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach hoc tap, nghien cuu tong hoc doanh hoa hoc ma hoi va ((nhan dan) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: so sach hoc tap, nghien cuu tong hoc doanh hoa hoc ma hoi va ((nhan dan) OR (phan dau))*.