If there's data on the page that only appears in a pop-up when you click a button, you can use the Click command to scrape it without any trouble.
1. Press the plus button and add a new Select command.
2. Click on the button which brings up the pop-up, to select the button.
3. Press the plus button and add a Click command.
4. ParseHub will ask you if this is a "next page" button. Click on "No" and it should recognize that the button uses AJAX. Choose to Continue executing the same template.
5. ParseHub will show the content displayed when you click on the button. Hold shift and hover over the command, and then click the plus button on the original Select command and add a new Select command.
6. Click on the element that you want to scrape from the pop-up to select it. ParseHub should automatically extract this data, and the active command should say Select and Extract.