ADO.NET RowFilter

[C# Programming]

Hi Experts
i using Visual Studio 2005.
I Fill a grid using Dataview in C#.NET winForms.
I Filter it with Dataview RowFilter then the result Come After Row Filter
Show in Different Grid now i want to Filter The Data from Second Grid not from first grid.
I mean to say that suppose e.g I Have Grid Result first Time
ID Name
1 Hello How R
2 i am fine
3 this is my book
4 this is C# Book
5 this is C# Example
6 Book is black


now i apply Row Filter on the 'this is'
dvs.RowFilter =Name like '%this is %'

now Result Come
ID Name
3 this is my book
4 this is C# Book
5 this is C# Example

Now i am again apply Row Filter not on the first case but apply on the second case.

now i apply Row Filter on the 'this is'
dvs.RowFilter =Name like '%Book%'
now Result Come this
I want this result set
ID Name
3 this is my book
4 this is C# Book
but result come
ID Name
3 this is my book
4 this is C# Book
6 Book is black

then how to fix this problem

this search within search in n time untill zero result is come....
Thank u
Dinesh