test.js

var req = require('request'),
    cheerio = require('cheerio'),
    async = require('async'),
    urls = ["http://google.com/", "http://test.de/", "http://bild.de/"];

function crawlUrl(url, callback) {
    "use strict";

    var array = [];

    req(url, function (error, response, body) {
        var $ = cheerio.load(body);

        $('strong').length;

        $('strong').each(function (i, item) {
            array.push($(this).text());

            if (i === $('strong').length) {
                callback(null, array);
            }
        });
    });
}

async.map(urls, crawlUrl, function (err, results) {
    "use strict";

    console.log(results);
    // results is now an array of the array for each url
});