Hi Miltos,
In the backend settings of each article, you will find two tabs: Listing Fields and Listing Information.
Listing Fields are defined in the file root/templates/ja_findus/etc/extrafields/listing.xml.
Listing Information are Joomla content fields that can be accessed under Backend >> Content >> Fields.
You can incorporate these additional fields and render them in the override layout file of the article: /templates/ja_findus/html/com_content/article/.
Depending on the article layout you are using, you will edit the corresponding PHP file: default.php, listing-1.php, and so on.
I hope this information is helpful.
