Hi Kim,
Create a non-persistent entity with a date attribute you will use for the search function.
Associate the two entities, each providing data to one grid, with the non-persistent entity.
Each grid's data source is a microflow that uses the date from the non-persistent entity to filter on an attribute of the entity in the grid.
The SearchHelper, I put in a Page parameter to be able to re-use the object when you are opening the same page.
The page looks like:
The Datasource Microflow:
Go Make It