We updated the lookup grid functionality in the back office module. Lookup grids could be used to select related data to the source object by a grid (as a modal) that appears. Source and filter settings now also apply to the lookup grid instead of the text input field on the form only.
Activate builder mode and go to the form component which specifies the related object data. Select the gear icon on the right at the component. The component settings appear and scroll down to the lookup grid settings. Choose a view reference for the lookup grid. To specify the set of data records in the lookup grid, you can insert the source and filter conditions.