final OptionalThing<FessUserBean> userBean) {
        final RankFusionSearcher[] availableSearchers = getAvailableSearchers();
        if (availableSearchers.length == 1) {
            return searchWithMainSearcher(availableSearchers[0], query, params, userBean);
        }
        return searchWithMultipleSearchers(availableSearchers, query, params, userBean);
    }

    /**