Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
nam thuc » nam thuoc, am thuc, nam thu
ky lang » ky dang, ky tang, tay lang
hieu va » lieu va, hieu qua
vat dan » va dan, van dan, vat ran
dan vai » dan va, dan tai, dan vat
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay

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 (doc sach)) ((ky lang) or (ky nang)) xa hoi. hieu va nam thuc vat dan vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ((ky lang) OR (ky nang)) xa hoi. hieu va nam thuc vat dan vai cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) ((ky lang) or (ky nang)) xa hoi. hieu va nam thuc vat dan vai cuu tre*.