Perhaps you should try some spelling variations:
nang noi » nang doc
noi hoat » toi hoat, doi hoat, voi hoat
ngha nam » nghia nam, nghe nam, nga nam
nam danh » nam dinh, nam dan
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
xa danh » va danh, dia danh, van danh
sai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang noi hoat. hieu ((ha nam) or (ngha nam)) thu ((xa danh) or (nam danh)) sai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang noi hoat. hieu ((ha nam) OR (ngha nam)) thu ((xa danh) OR (nam danh)) sai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang noi hoat. hieu ((ha nam) or (ngha nam)) thu ((xa danh) or (nam danh)) sai cua tre*.