Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cau tren » cu tren, dau tren, ca tren
hieu ve » hieu va, hieu van
ve chat » va chat, van chat
xang ma » tang ma, nang ma, sang ma
dinh va » dinh van, dinh ve, tinh va
cuu tre » cua tre, cau treo
tuc va » thuc va, truc va, duc va
y xang » ty xang

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 y xang ma hoa. hieu ve chat ((tuc va) OR (tuc xa)) dinh va ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y xang ma hoa. hieu ve chat ((tuc va) OR (tuc xa)) dinh va ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y xang ma hoa. hieu ve chat ((tuc va) OR (tuc xa)) dinh va ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: toc sach y xang ma hoa. hieu ve chat ((tuc va) OR (tuc xa)) dinh va ((cuu tre) or (cau tren))*.