To access the filter option, click on Make a Zap and you will be directed to another view where you can also build your Zap.
Once connected to your GetAccept account, you've chosen for instance in my example: Event New document. Click on the + symbol below and choose filter.
Here you can create a customized filter of what you want to happen for certain types of events.
You can choose different filters based on the Document that is being sent or the Recipient that is receiving the document.
To do this, you can choose for example: Only continue if... Document Sender Name - Text Contains - Documen Recipients First name.
Click Continue to add the action application.