Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
sach ky » sac ky, sach y, sach ty
lang ha » long ha
lang xa » dang xay, lang van
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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 ((lang xa) or (lang ha)) hoi. hieu ((ve cham) or (va cam)) luc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((lang xa) OR (lang ha)) hoi. hieu ((ve cham) OR (va cam)) luc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((lang xa) or (lang ha)) hoi. hieu ((ve cham) or (va cam)) luc va hanh vi cua tre*.