Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
hieu van » hieu va, thien van, lieu va
van quan » van ban
nang ma » tang ma, sang ma, nang cao
sach va » sach xa, sach ha, sach dao
van cam » van nam, van lam, van cau
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
sach v » sach y, sach 2, sach vay
ly cua » le cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((sach v) OR (sach va)) nang ma hoi. hieu van cam xuc ((van thanh) or (van quan)) ly cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((sach v) OR (sach va)) nang ma hoi. hieu van cam xuc ((van thanh) OR (van quan)) ly cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((sach v) OR (sach va)) nang ma hoi. hieu van cam xuc ((van thanh) or (van quan)) ly cua tre".
• Adding a wildcard symbol may retrieve word variants: doc ((sach v) OR (sach va)) nang ma hoi. hieu van cam xuc ((van thanh) or (van quan)) ly cua tre*.