Perhaps you should try some spelling variations:
thanh hoi » thanh hoai, thanh hoa, thanh hai
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
hoi cua » hoi chuc
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va
sach v » sach va, sach y, sach vay
soc va » hoc va, loc va, doc va
sach 2 » sach y
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach v) or (sach 2)) nang x hoi. ((hieu ve) OR (hieu van)) cham soc va thanh hoi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach 2)) nang x hoi. ((hieu ve) OR (hieu van)) cham soc va thanh hoi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach v) or (sach 2)) nang x hoi. ((hieu ve) OR (hieu van)) cham soc va thanh hoi cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach 2)) nang x hoi. ((hieu ve) OR (hieu van)) cham soc va thanh hoi cua tre*.