Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
cua triet » cua viet, su triet, va triet
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach ty, sach kem
van cau » van dau, van hau, van chat
cau luc » cau truc, cau phuc
cua tre » cua te, cuu tre, dua tren
luc va » duc va, tuc va, loc va

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: tu ((sach ky) OR (sach y)) nang x ho. hieu van cau luc va thanh vai ((cua tre) OR (cua triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach y)) nang x ho. hieu van cau luc va thanh vai ((cua tre) or (cua triet))~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sach y)) nang x ho. hieu van cau luc va thanh vai ((cua tre) or (cua triet))*.