Perhaps you should try some spelling variations:
dung sai » dung tai, dung va, dung dat
sach thu » sach thue, sach thieu, sach tham
nam dung » nam vung, nam dong, am dung
sai cua » dai cua, hai cua, lai cua
thu nam » tu nam, thu nhap, thu nhat
nang ma » tang ma, sang ma, nang cao
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
le nam » ly nam, he nam, te nam
ma hoi » mai hoi, xa hoi, ma hoa
le na » le va, le ta, le ha

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) or (sach thu)) nang ma hoi. hieu ((le nam) or (le na)) thu nam dung sai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach thu)) nang ma hoi. hieu ((le nam) OR (le na)) thu nam dung sai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach thu)) nang ma hoi. hieu ((le nam) or (le na)) thu nam dung sai cua tre*.