Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
sach doi » sach hoi, sach moi, sach dao
cong coc » cong cuoc, cong cac, cong co
coc danh » hoc danh, cuon danh, chuc danh
danh hoa » thanh hoa, khanh hoa, nganh hoa
thai van » thi van, thanh van, thai vung
nhan dan » phan dau, gian dan, nhan tai
hang tai » hang va, dung tai
so sach » so sanh, bo sach, co sach
doi tap » doi tac, doi dap, doi tai
xa thai » ca thai, a thai, da thai
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: so sach doi tap, nghien cua cong coc danh hoa hoc xa thai van ((nhan dan) or (hang tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach doi tap, nghien cua cong coc danh hoa hoc xa thai van ((nhan dan) OR (hang tai)).
• Adding a wildcard symbol may retrieve word variants: so sach doi tap, nghien cua cong coc danh hoa hoc xa thai van ((nhan dan) or (hang tai))*.