Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
dang xay » dang van, van xay
va chat » van chat, va phat, cao chat
vai cua » dai cua, hai cua, lai cua
bo sach » co sach, hoc sach
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: bo sach y ((dang xay) or (nang x)) hoi. hieu va chat ((xuc va) or (tuc va)) thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo sach y ((dang xay) OR (nang x)) hoi. hieu va chat ((xuc va) OR (tuc va)) thanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: bo sach y ((dang xay) or (nang x)) hoi. hieu va chat ((xuc va) or (tuc va)) thanh vai cua tre*.