Windows Report (rdlc) How to filter a grouping by the count of the child items?

I have a simple report, one field as row, one field as value. The data is grouped by the row field.

I want to display only the rows where there are more than 1 value items (thus hiding where there is only 1 value item).

Anyone knows how to do it? If more details are needed ask开发者_开发知识库 away

in your dataset there is the ability to do filters, you can just filter the value for > 0