Is any way to manage keywords in Admob for Windows Phone 7?

I am using official Admob Windows Phone 7 SDK (latests 4.0.4 beta version) in my application published in marketplace. And I have extremely low click rate (below 1 click for a thousand of ad shows). So I am trying to find ways to improve this value and most logical way seems to use keywords for context-sensitive ads.

But I just can't find where to manage keywords in my app! I've ch开发者_JAVA百科ecked online docs for SDK and examples and there is nothing about it. Can someone point me in right direction?