Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
va thanh » gia thanh, ban thanh, va tinh
so sach » so sanh, bo sach, co sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
hieu ve » hieu va, hieu van
cua tre » cuu tre, cua triet, dua tren
ve cap » ve cac, le cap, ve cai
cuu va » cuu van, cuu ve
cua te » cua tu
x hoi » o hoi, x ho, 5 hoi

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 tu nang ((x hoi) OR (xa hoi)). hieu ve cap cuu va thanh vai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach tu nang ((x hoi) OR (xa hoi)). hieu ve cap cuu va thanh vai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach tu nang ((x hoi) OR (xa hoi)). hieu ve cap cuu va thanh vai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: so sach tu nang ((x hoi) OR (xa hoi)). hieu ve cap cuu va thanh vai ((cua tre) or (cua te))*.