How to Search the Facebook Group
You can use the Search box on the right side of the Facebook Group to search for specific posts within the group. Simply type your search term in the search box then hit Enter/Return. Here's a screenshot for your reference:
If you're using the Facebook app on your iPhone, you can use the Search box on the top right to look for posts with your search term. Here's a screenshot for this:
To make sure you're posting your photos in the group, please click on iPhone Photo Academy or Digital Camera Mastery first and then click the Photo icon from there. See How to Post in the Facebook Group for more information.