How to exclude items from search api solr by negative keywords field Drupal 8, Search API SOLR.

I'd like to not return nodes if there are any matches between a field of negative keywords (on the node) and the query string the user has entered.

Module search_api_solr currently set up with several fields, matching in node titles, body and keyword fields.

e.g.
node titled "I can't find my elephant" with a negative keyword field containing "wallet" to not show up in a search "I can't find my wallet".
You don't need to do this in solr, you can do it in the query or with views filters.

Something like this:

$solrIndex = \Drupal::entityTypeManager()-&gt;getStorage('search_api_index')-&gt;load('global');
$query = $solrIndex-&gt;query();
$query-&gt;addCondition('title', $search_string);

$search_terms = explode(' ', $search_string);

// Don't match items where elements in the title match the stop words
// for an entity.
foreach ($search_terms as $term) {
  $query-&gt;addCondition('field_stop_words', $term, '&lt;&gt;');
}