Perhaps you should try some spelling variations:
dang xay » dang van, van xay
dinh vai » dinh van, dinh vi, dinh va
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
tu sach » thu sach, su sach, te sach
cac toc » cac toi, cac thoi
vai cua » dai cua, hai cua, lai cua
va dinh » van dinh, va kinh, va tinh
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
lang xa » lang ha, lang van

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 ((dang xay) or (lang xa)) hoi. hieu ve ((cac toc) or (cac nuoc)) va dinh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((dang xay) OR (lang xa)) hoi. hieu ve ((cac toc) OR (cac nuoc)) va dinh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((dang xay) or (lang xa)) hoi. hieu ve ((cac toc) or (cac nuoc)) va dinh vai cua tre*.