First inspect the DOM to view the HTML structure for the element you want to select. Next navigate to advanced mode by clicking on the data model view and then on 'Advanced'.
From here, adjust the CSS selectors to extract the element you want. A great workaround to get you most of the way there with your CSS is to select an element close to the one you want on the page, then tweak the CSS selector.
Next click on 'attributes':
And from here select 'hidden data':
click Apply, and then reopen the attributes extractor window again. You will be able to check which hidden attributes exactly you want extracted from your element.
You can spawn more data types by clicking the plus icon on the toolbar.
You can view a video for more help here.