Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
tra nang » thi nang, kha nang, da nang
sieu van » hieu van, su van, lieu va
tu nang » tru nang, tu nong, tu nano
nam duc » nam duoc, pham duc, nam thuc
va tich » va tinh, va dich
va cua » va chua, via cua, ca 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) or (doc sach)) ((tu nang) or (tra nang)) x hoi. sieu van nam duc va tich va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ((tu nang) OR (tra nang)) x hoi. sieu van nam duc va tich va cua te.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (doc sach)) ((tu nang) or (tra nang)) x hoi. sieu van nam duc va tich va cua te*.