Hi,
I'm currently trying to build an app which can filter an ADS table into a collection in the app using mutliple criteria.
This is the formula I currently have to filter by Project Number and this works.

The project number field is mandatory so will always need to be filtered by that first.
I would also like to add an option to filter by the below fields too, but these are not mandatory so some may be left empty when filtering. I can not find a way of doing this so any help would be apprectiated.

Thanks in advance.