Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hoi » van hoa, van hoc, van loi
van hoe » van hoa, van hoc, van hieu
hieu va » lieu va, hieu qua
va tham » van tham, va cham, va thanh
sach ky » sac ky, sach y, sach ty
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
de cua » le cua, te cua, dieu 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 nang ((van hoi) or (van hoe)). hieu va tham ((xuc va) OR (tuc va)) hanh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ((van hoi) OR (van hoe)). hieu va tham ((xuc va) OR (tuc va)) hanh de cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang ((van hoi) or (van hoe)). hieu va tham ((xuc va) OR (tuc va)) hanh de cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ((van hoi) or (van hoe)). hieu va tham ((xuc va) OR (tuc va)) hanh de cua tre*.