Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh vi » hanh vi, thanh va, thanh ve
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cao duc » dao duc, cao suc, giao duc
cua tre » cuu tre, cua triet, dua tren
duc van » duc va, duc tan, duc manh
van cao » van dao, van bao, van hao
nang xa » nang x, lang xa, nang ma
cua te » cua tu

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 y ((nang xa) or (nang cao)) hoi. hieu van cao duc van thanh vi ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang cao)) hoi. hieu van cao duc van thanh vi ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (nang cao)) hoi. hieu van cao duc van thanh vi ((cua tre) or (cua te))*.