JSFiddle - React, Tailwind, and code Playground

JavaScript

function getCommon(array1,array2){
    var result = new Array();
    for (i=0; i<array1.length; i++) {
        for (j=0; j<array2.length; j++) {
            if (array1[i] == array2[j] && jQuery.inArray(array1[i],result) == -1)
                result.push(array1[i]);
        }
    }
    return result;
}

var str1 = "apple banana cherry damson";
var str2 = "apple elderberry cherry fig";

var array1 = str1.split(/\b/);
var array2 = str2.split(/\b/);

var commonWords = getCommon(array1,array2);
alert(commonWords);