Perhaps you should try some spelling variations:
thanh dao » thanh dat, thanh dam, thanh do
nang lai » nang tai, mang lai, nang cai
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
dao cua » dai cua, day cua, dan cua
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
hieu ve » hieu van
lai hoa » dai hoa, loai hoc
xuc va » duc va, luc va, xac va
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: so sach ky nang lai hoa. ((hieu ve) or (hieu va)) cam ((xuc va) OR (tuc va)) thanh dao cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang lai hoa. ((hieu ve) OR (hieu va)) cam ((xuc va) OR (tuc va)) thanh dao cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang lai hoa. ((hieu ve) or (hieu va)) cam ((xuc va) OR (tuc va)) thanh dao cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang lai hoa. ((hieu ve) or (hieu va)) cam ((xuc va) OR (tuc va)) thanh dao cua tre*.