Perhaps you should try some spelling variations:
doanh khoa » toan khoa
hoc doanh » hoa doanh, hoc danh, hoc dan
toc sach » hoc sach, doc sach, thuoc sach
sach dao » lanh dao
khoa hoc » hoa hoc
dao tap » dao tao, dao tay, dao gap
va nhan » van nhan, va phan, va nha
mo hoc » mon hoc, co hoc
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: toc sach dao tap, nghien cuu mo hoc doanh khoa hoc ma hoi ((va nhan) or (ca nhan)) dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach dao tap, nghien cuu mo hoc doanh khoa hoc ma hoi ((va nhan) OR (ca nhan)) dan.
• Adding a wildcard symbol may retrieve word variants: toc sach dao tap, nghien cuu mo hoc doanh khoa hoc ma hoi ((va nhan) or (ca nhan)) dan*.