SierraBravoFour on "Add credit to allowed search fields"

I would like to add the Credit field as a searchable element. At first I tried passing a custom array to the printSearchForm function, but that did not have any effect.Ex:

$query_fields = array("desc","custom_data","tags","credit");
printSearchForm(NULL,'search',NULL,NULL,NULL,$query_fields,NULL,false);


Next, I tried adding it directly to the search_fields option in the DB. No luck there either.

Eventually, I was able to get it to work by adding credit to the search_fields option in the DB and also modifying the search engine construct of the core class-search.php file with the following:
$this->search_structure['credit'] = gettext('Credit');

So my question is, is there a way to add Credit to the list of fields to search without modifying the core search file?

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