Demonstrates how to query all search results using SharePoint 2013 Search REST API

sp.rest.search.js

function search(webUrl,queryText,rowLimit,startRow,allResults)
{
    var allResults = allResults || [];
    var url = webUrl + "/_api/search/query?querytext='" + queryText + "'&rowlimit=" + rowLimit + "'&startrow=" + startRow;
    return $.getJSON(url).then(function(data) {
           var relevantResults = data.PrimaryQueryResult.RelevantResults;
           allResults = allResults.concat(relevantResults.Table.Rows);
           if (relevantResults.TotalRows > startRow + relevantResults.RowCount) {
               return search(webUrl,queryText,rowLimit,startRow+relevantResults.RowCount,allResults);
           }    
           return allResults;
    });
}