Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
van thanh » ban thanh, van tuan
thu sach » tu sach, thuat sach, thuoc sach
sach nay » sach hay, sach vay, sach nang
nay lang » nam lang, tay lang, nhan lang
hieu van » hieu va, thien van
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach nay lang xa hoi. ((hieu ve) or (((hieu van) or (lieu va)))) cam duc van thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach nay lang xa hoi. ((hieu ve) OR (((hieu van) OR (lieu va)))) cam duc van thanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach nay lang xa hoi. ((hieu ve) or (((hieu van) or (lieu va)))) cam duc van thanh dai cua tre*.