By default, when an Axsy Smart Form has been completed, any fields that have not been answered will not be displayed in the Form Response View. To view these empty fields, you need to use the field toggle furthest to the right side of the screen.
Hidden fields will always be empty when sent back to Salesforce in the Form Response. For more information, please see this article: Difference between 'Hidden' and 'Invisible' Elements
If Elements have been set to 'Invisible' Mode under the Defaults tab of the Edit Properties Window, there is an option to toggle whether you want to view these fields and their values via the toggle to the left.
Access a Form Response Object Record
1. The default view for a Form Response means that both the field toggles are active, so empty and invisible fields are hidden.
2. Select the toggle on the right once to display all empty fields as well as non-empty fields.
3. Select the toggle on the left side to display invisible fields.