I believe it's because as I see the results content display is turned off, therefore the change is not visible. So first of all, you need to make sure it's turned on. Go to the Layout Options -> Results layout panel and turn on the “Show description in results?” option: https://i.imgur.com/Pj0lnKu.png
After that, the content should become visible on the front-end.
In the second code you provided I cannot actually see any custom fields parsed, but I guess you want the social icons HTML part to be appended to the end of the description:Best,
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