Perhaps you should try some spelling variations:
khanh chong » khanh phong, nhanh chong, thanh chuong
nghien cac » nghiep cach, nghien cuu, nghiep cay
hoa khanh » hoa thanh, hoa phan, hoa hinh
giang dan » gian dan, giang day, giang van
mach hoc » cach hoc, dich hoc, anh hoc
cac cong » cua cong
cong hoa » dong hoa, dong hoc, hang hoa
ca giang » cua giang, ha giang, ma giang
su mach » su sach
duoc xa » duoc ma, duoc va, duoc ha
hoc xa » hoc ma
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: su mach hoc tap, nghien cac cong hoa khanh chong ((hoc xa) or (duoc xa)) hoi ca giang dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su mach hoc tap, nghien cac cong hoa khanh chong ((hoc xa) OR (duoc xa)) hoi ca giang dan.
• Adding a wildcard symbol may retrieve word variants: su mach hoc tap, nghien cac cong hoa khanh chong ((hoc xa) or (duoc xa)) hoi ca giang dan*.