Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
van thanh » van tuan
hieu van » hieu va, thien van, lieu va
te sach » toc sach
van bac » van ban, van bao, van hac
ty nang » ky nang, ty hang, ly nang
bac do » ban do, bac bo, bac ho
vi cua » vai cua, di 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: te sach ((ty nang) or (ty xang)) x hoi. hieu van bac do ((van thanh) OR (ban thanh)) vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ty xang)) x hoi. hieu van bac do ((van thanh) OR (ban thanh)) vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty nang) or (ty xang)) x hoi. hieu van bac do ((van thanh) OR (ban thanh)) vi cua te".
• Adding a wildcard symbol may retrieve word variants: te sach ((ty nang) or (ty xang)) x hoi. hieu van bac do ((van thanh) OR (ban thanh)) vi cua te*.