Perhaps you should try some spelling variations:
kinh de » kinh te, kinh do, kinh ve
luc qua » luc quan, luc cua, luc nua
sach ky » sac ky, sach ty, sach kem
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
de cua » le cua, te cua, dieu cua
de coc » de hoc, de cac
de co » ke co

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach y)) nang xa hoi. hieu ((de coc) OR (de co)) luc qua kinh de cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach y)) nang xa hoi. hieu ((de coc) or (de co)) luc qua kinh de cua tre~".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sach y)) nang xa hoi. hieu ((de coc) or (de co)) luc qua kinh de cua tre*.