Filtering DataGrid is Slow at first....?

Hi Guy's I'm struggeling with the following question.

I have a form with a Datagrid which i would like to filter:

BindingSource.Filter = "Name LIKE '%" & txtFind.Text & "%'"

This is the code used to filter the datagridview, where the datasource=BindingSource. The thing thats bugging me about it is that it takes ages to filter when the bindingsource is unfiltered, but when it is filtered and you run this code again with a different search it runs quickly.

Does anyone know where the problem could be?

Thanks in advance!