Perhaps you should try some spelling variations:
thanh di » thanh doi, thanh de, thanh do
so sach » so sanh, bo sach, co sach
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
dang ha » dong ha, dung ha, lang ha
ky dang » ky nang, ky danh
tuc va » thuc va, truc va, tuc xa
di cua » dai cua, doi cua, de cua
ac va » tac va, bac va, mac va

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky dang ha noi. ((hieu ve) or (hieu va)) cam ((ac va) or (tuc va)) thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky dang ha noi. ((hieu ve) OR (hieu va)) cam ((ac va) OR (tuc va)) thanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach ky dang ha noi. ((hieu ve) or (hieu va)) cam ((ac va) or (tuc va)) thanh di cua tre*.