Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
ky dang » ky nang, ky danh
ky tang » ky nang, kho tang, ky trong
hieu ca » hieu cac, hieu cua, hieu va
ky lang » ky nang, tay lang
thuc va » thuc vat, thuc dan, thuc day
dan vai » dan va, dan tai, dan vat
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
ca nam » cua nam, cai nam, ha nam
va dan » ca dan, va dao, va dau

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

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