Perhaps you should try some spelling variations:
dang xay » dang van, van xay
hoc sach » hoc sinh, hoc cac, hoc anh
nam thuc » nam thuoc, am thuc, nam thu
toc sac » toc sach, toc san, doc sach
vai cuu » vai cua
dan vai » dan va, dan tai, dan vat
thuc va » thuc vat, thuc dan, thuc day
hieu va » lieu va, hieu qua
lang xa » lang ha, lang van
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay
va dan » ca dan, va dao, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sac) OR (hoc sach)) ky ((lang xa) or (dang xay)) hoi. hieu va nam thuc va dan vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sac) OR (hoc sach)) ky ((lang xa) OR (dang xay)) hoi. hieu va nam thuc va dan vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sac) OR (hoc sach)) ky ((lang xa) or (dang xay)) hoi. hieu va nam thuc va dan vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sac) OR (hoc sach)) ky ((lang xa) or (dang xay)) hoi. hieu va nam thuc va dan vai cuu tre*.