Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
thanh hoa » thanh pho
sach hoc » cach hoc, sach hoi, mach hoc
dong cac » duong cac, dung cac, cong cac
dong bac » dong bang, dong luc, dong hoc
nhan dan » phan dau, gian dan, nhan tai
su sach » so sach, vu sach
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 sach hoc tap, nghien thu ((dong cac) or (dong bac)) thanh hoa hoc xa hoi ca nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach hoc tap, nghien thu ((dong cac) OR (dong bac)) thanh hoa hoc xa hoi ca nhan dan.
• Adding a wildcard symbol may retrieve word variants: su sach hoc tap, nghien thu ((dong cac) or (dong bac)) thanh hoa hoc xa hoi ca nhan dan*.