getRelevanceSelection example

if (empty($tables)) {
            return null;
        }

        $query = $this->buildQueryFromKeywords($keywords, $tables);

        $this->addToleranceCondition($query);

        $query->select(
            [
                'a.id as product_id',
                '(' . $this->getRelevanceSelection() . ') as ranking',
            ]
        );

        $enableAndSearchLogic = $this->config->get('enableAndSearchLogic', false);
        if ($enableAndSearchLogic) {
            $this->addAndSearchLogic($query, $term);
        }

        return $query;
    }