Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
sach doi » sach hoi, sach moi, sach dao
cong cac » cuong cac, cong tac, cong cau
cac danh » cac doanh, cac dan, cac dang
danh hoa » thanh hoa, khanh hoa, nganh hoa
nhan dan » phan dau, gian dan
nhan tai » hang tai, van tai, toan tai
su sach » so sach, vu sach
doi tap » doi tac, doi dap, doi tai
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 sach doi tap, nghien cua cong cac danh hoa hoc xa hai van ((nhan dan) or (nhan tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach doi tap, nghien cua cong cac danh hoa hoc xa hai van ((nhan dan) OR (nhan tai)).
• Adding a wildcard symbol may retrieve word variants: su sach doi tap, nghien cua cong cac danh hoa hoc xa hai van ((nhan dan) or (nhan tai))*.