Perhaps you should try some spelling variations:
doanh khoa » toan khoa
hoc doanh » hoa doanh, hoc danh, hoc dan
khoa hoc » hoa hoc
gian dan » gian lang
te sach » toc sach
hoi tai » hoc tai, hoi trac
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
ca gian » ca giang, ca giao, va gian
ma hoi » mai hoi, xa hoi, ma 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: te sach ((hoc tap) or (hoi tai)), nghien cuu mon hoc doanh khoa hoc ma hoi ca gian dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((hoc tap) OR (hoi tai)), nghien cuu mon hoc doanh khoa hoc ma hoi ca gian dan.
• Adding a wildcard symbol may retrieve word variants: te sach ((hoc tap) or (hoi tai)), nghien cuu mon hoc doanh khoa hoc ma hoi ca gian dan*.