Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
va dan » ca dan, va dao, va dap
va dau » va dao
di cua » dai cua, doi cua, de cua
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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 v nang x hoi. hieu va cac luc ((va dan) or (va dau)) di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach v nang x hoi. hieu va cac luc ((va dan) OR (va dau)) di cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach v nang x hoi. hieu va cac luc ((va dan) or (va dau)) di cua te*.