Get cookie by name

I have a getter to get the value from a cookie.

Now I have 2 cookies by the name shares= and by the name obligations= .

I want to make this getter only to get the values from the obligations cookie.

How do I do this? So the for splits the data into separate values and puts it in an array.

 function getCookie1() {
    // What do I have to add here to look only in the "obligations=" cookie? 
    // Because now it searches all the cookies.

    var elements = document.cookie.split('=');
    var obligations= elements[1].split('%');
    for (var i = 0; i < obligations.length - 1; i++) {
        var tmp = obligations[i].split('$');
        addProduct1(tmp[0], tmp[1], tmp[2], tmp[3]);
    }
 }