Elasticsearch performance is not increasing by adding new nodes

Elastic Stack Elasticsearch
4

index size is 113 GB.
it doesn't matter what kind of query we run, every type of query that runs on this cluster has the same result, It means the time the query takes on one node is approximately same as it runs on 3 nodes, that's the main problem. the following query is an example:

    QueryBuilder query = boolQuery()
                   .filter(termsQuery("DEBTOR",ibns))
                   .filter(rangeQuery("CREATIONDATETIME").from(dateFrom)
                   .to(dateTo)
                   .includeLower(true)
                   .includeUpper(true));

    SortBuilder sort = SortBuilders.fieldSort("CREATIONDATETIME").order(SortOrder.DESC);

    SearchResponse searchResponse = ElasticOperation.transportClient
            .prepareSearch("index_name")
            .setSearchType(SearchType.QUERY_THEN_FETCH)
            .setSize(1000)
            .setQuery(query)
            .addSort(sort)
            .execute()
            .actionGet();