Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
ky sang » ky dang, ky tang, duy sang
vai cua » dai cua, hai cua, lai cua
tao hoi » tao khoi, tao boi, tay hoi
hieu ve » hieu van
dan vai » dan va, dan tai, dan vat
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
va dan » ca dan, va dao, va dau
cua te » cua tu
tuc va » thuc va, truc va, tuc xa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky sang) OR (ky nang)) tao hoi. ((hieu ve) or (hieu va)) cac tuc va dan vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky sang) OR (ky nang)) tao hoi. ((hieu ve) OR (hieu va)) cac tuc va dan vai cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky sang) OR (ky nang)) tao hoi. ((hieu ve) or (hieu va)) cac tuc va dan vai cua te*".