setSiteRestriction not working on a specific website

On my search I want开发者_如何学Go to filter results to my website, I tried the following:

webSearch.setSiteRestriction("orkutmanager.net");

But it doesn't work... If I set it to amazon.com

webSearch.setSiteRestriction("amazon.com");

It works.

Searching on Google's main page it works normally, e.g. orkut site:orkutmanager.net

Is it a bug? Is there a workaround?

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I've created a custom search and added the id instead of the url

webSearch.setSiteRestriction("017220008487069298117:xgy2xbuc2io");