Perhaps you should try some spelling variations:
mach hoc » cach hoc, dich hoc, anh hoc
cuu dong » cuu cong, cuu tong, cuu long
co thanh » cho thanh, o thanh, co tranh
cong hoc » dong hoc, cong hoa, cong coc
nhan dan » gian dan, nhan tai
phan dau » phan tu, hang dau
su mach » su sach
hai van » thai van, ha van, hai tan
hoc xa » hoc ma
xa hai » xa thai, xua hai, xa hoi

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 dong co thanh cong hoc xa hai van ((nhan dan) or (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su mach hoc tap, nghien cuu dong co thanh cong hoc xa hai van ((nhan dan) OR (phan dau)).
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien cuu dong co thanh cong hoc xa hai van ((nhan dan) or (phan dau))*.