Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thanh vi » hanh vi, thanh va, thanh ve
xay hoi » xa hoi, tay hoi, cay phoi
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
ky dang » ky danh
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, xac va
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: toc sach ((ky dang) or (ky nang)) xay hoi. hieu vu cham ((xuc va) or (luc va)) thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ky dang) OR (ky nang)) xay hoi. hieu vu cham ((xuc va) OR (luc va)) thanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ky dang) or (ky nang)) xay hoi. hieu vu cham ((xuc va) or (luc va)) thanh vi cua tre*.