Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
toc sach » hoc sach, doc sach, thuoc sach
pham duy » pham duc
hai cua » thai cua, dai cua, hoi cua
duy gia » duy gian, duc gia, quy gia
va pham » van pham, va phat, va phap
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
mai hoi » mai khoi, dai hoi, lai hoi
ma hoi » xa hoi, ma hoa, me hoi
v nang » va nang, vu nang, van nang

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) OR (toc sach)) v nang ((ma hoi) or (mai hoi)). hieu va pham duy gia thanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) v nang ((ma hoi) OR (mai hoi)). hieu va pham duy gia thanh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) v nang ((ma hoi) or (mai hoi)). hieu va pham duy gia thanh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) v nang ((ma hoi) or (mai hoi)). hieu va pham duy gia thanh hai cua tre*.