final String[] relatedQueries = relatedQueryHelper.getRelatedQueries(params.getQuery());
            buf.append(",\"related_query\":");
            buf.append(escapeJson(relatedQueries));
            final String[] relatedContents = relatedContentHelper.getRelatedContents(params.getQuery());
            buf.append(",\"related_contents\":");
            buf.append(escapeJson(relatedContents));
            buf.append(',');