Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
hieu ve » hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky dang » ky nang, ky danh
ky tang » ky nang, kho tang, ky trong
cuu tre » cua tre, cau tren, cau treo
tro ca » tro cua, tro cap, tho ca
ca dan » cac dan, ca dao
dan va » doan va, dan ca, ban va
va cuu » va cau, va chu, va huu

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 tang) OR (ky dang)) mai hoi. ((hieu ve) or (hieu va)) cac tro ca dan va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky tang) OR (ky dang)) mai hoi. ((hieu ve) OR (hieu va)) cac tro ca dan va cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky tang) OR (ky dang)) mai hoi. ((hieu ve) or (hieu va)) cac tro ca dan va cuu tre*".