title: Check if string contains set of other string
body: <p>I want to check if string one in array contain the letters from words in string 2. Here's my example array:</p>
  
  <p><code>(["Floor", "far"]);</code></p>
  
  <p>function should return false because "a" is not in string "Floor" 
  But for array like this: </p>
  
  <p><code>(["Newbie", "web"]);</code></p>
  
  <p>It should return true because all of letters from "web" are in "Newbie".</p>
  
  <p>Here's my code so far...</p>
  
  <pre><code>function mutation(arr) {
      var newArr = [];
      for (i=0; i&lt;arr.length; i++) {
          newArr.push(arr[i].toLowerCase().split(""));
      }
      for (i=0; i&lt;newArr.length; i++) {
          for (j=0; j&lt;newArr[i].length; j++) {
              console.log(newArr[0][j]+ (newArr[1][j]));
      }
    }
  }
  mutation(["Newbie", "web"]);
  </code></pre>
  
  <p>I know that it won't work and I'm out of ideas how to make it. I try to make a set of all letters in two array and compare them. If there is at least one <em>false</em> the function should return false. Should I nest <em>indexOf()</em> method somewhere?</p>