ModX TV parameter doesn't display in snippet
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I have created a TV parameter representing a DropDownList Menu. But when I call it in a snippet via Modx API It doesn't display at all.

here's the TV I made![enter image description here][1]


  [1]: http://i.stack.imgur.com/DCGm9.jpg

a here is how I call it

    $name=$buf['title'].' ( цвет: '.$modx->documentObject['material'].' )';

What am I doing wrong? Thx