Perhaps you should try some spelling variations:
dung sai » dung tai, dung va, dung dat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cam luc » cam xuc, cau luc
va dung » van dung, va duong, vat dung
sai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
luc va » duc va, tuc va, loc va

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