Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
toc sach » hoc sach, doc sach, thuoc sach
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
dang ma » dang mau, dang mam, dang mat
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
y dang » ky dang, 2 dang, _ dang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) y dang ma hoa. hieu van nam ((xuc va) or (tuc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) y dang ma hoa. hieu van nam ((xuc va) OR (tuc va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) y dang ma hoa. hieu van nam ((xuc va) or (tuc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) y dang ma hoa. hieu van nam ((xuc va) or (tuc va)) hanh vai cua tre*.