Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
toc sach » hoc sach, doc sach, thuoc sach
dung tay » dung tai, dung may, vung tay
tay thai » lay thai, toc thai, y thai
dinh va » dinh van, dinh ve, tinh va
ty dung » tay dung, ly dung, te dung
cuu tre » cua tre, cau tren, cau treo
xuc va » duc va, tuc va, luc va
va cuu » va cau, va chu, va huu

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)) ty dung tay thai. hieu van nam ((xuc va) or (tuc xa)) dinh va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty dung tay thai. hieu van nam ((xuc va) OR (tuc xa)) dinh va cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ty dung tay thai. hieu van nam ((xuc va) or (tuc xa)) dinh va cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ty dung tay thai. hieu van nam ((xuc va) or (tuc xa)) dinh va cuu tre*.