Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
cac tuc » cac toc, cac tu, cac tac
ky dang » ky nang, ky danh
mat hoi » mai hoi, sat hoi, luat hoi
hieu ve » hieu van
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
va cua » va chua, via cua, ca cua
dan va » doan va, dan ca, ban va
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 dang ((mat hoi) OR (mat troi)). ((hieu ve) or (hieu va)) cac tuc va dan va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang ((mat hoi) OR (mat troi)). ((hieu ve) OR (hieu va)) cac tuc va dan va cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky dang ((mat hoi) OR (mat troi)). ((hieu ve) or (hieu va)) cac tuc va dan va cua te*".