Perhaps you should try some spelling variations:
thuoc mach » thuoc sach, thuong mach, thuoc ma
mach hoc » cach hoc, dich hoc, anh hoc
cuu cong » cua cong, thu cong, cac cong
cong hoc » dong hoc, cong hoa, cong coc
van nhan » van phan, van thanh, danh nhan
hoc tan » hoc tang, hoc dan, hoc tai
tan hoa » van hoa, tap hoa, tan ha
va nhan » ca nhan, va phan, va nha
hoc xa » hoc ma

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc mach hoc tap, nghien cuu cong hoc tan hoa hoc xa hoi ((va nhan) or (van nhan)) dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc mach hoc tap, nghien cuu cong hoc tan hoa hoc xa hoi ((va nhan) OR (van nhan)) dan.
• Adding a wildcard symbol may retrieve word variants: thuoc mach hoc tap, nghien cuu cong hoc tan hoa hoc xa hoi ((va nhan) or (van nhan)) dan*.