Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
hieu van » hieu va, thien van, lieu va
tri nang » thi nang, tra nang, tri bang
doc sach » hoc sach, nuoc sach, dac sac
tu nang » tru nang, tu nong, tu nano
nam duc » nam duoc, pham duc, nam thuc
va tinh » may tinh
tinh va » tich va, trinh van, trinh vat
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 (tri nang)) x hoi. hieu van nam duc va tinh va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ((tu nang) OR (tri nang)) x hoi. hieu van nam duc va tinh va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (doc sach)) ((tu nang) or (tri nang)) x hoi. hieu van nam duc va tinh va cua te".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (doc sach)) ((tu nang) or (tri nang)) x hoi. hieu van nam duc va tinh va cua te*.