Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van cua » vang cua, ban cua, dan cua
truc va » thuc va, thuc vat, trung va
van cam » van nam, van lam, van cau
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
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 y ((nang ma) or (sang ma)) hoi. hieu van cam ((tuc xa) or (truc va)) thanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((nang ma) OR (sang ma)) hoi. hieu van cam ((tuc xa) OR (truc va)) thanh van cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y ((nang ma) or (sang ma)) hoi. hieu van cam ((tuc xa) or (truc va)) thanh van cua tre*.