Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
dang xay » dang van, van xay
cau treo » cau theo, cau tren, cau triet
xay hoi » xa hoi, tay hoi, cay phoi
thuc ca » thuc cua, thuc can, thuc cao
dan vai » dan va, dan tai, dan vat
vai cau » va cau, van cau, vai cac
y dang » ky dang, 2 dang, _ dang
ca dan » cac dan, ca dao

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) OR (hoc sach)) y dang xay hoi. hieu ((van nam) or (ha nam)) thuc ca dan vai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) y dang xay hoi. hieu ((van nam) OR (ha nam)) thuc ca dan vai cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) y dang xay hoi. hieu ((van nam) or (ha nam)) thuc ca dan vai cau treo".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) y dang xay hoi. hieu ((van nam) or (ha nam)) thuc ca dan vai cau treo*.