Low Harvest URL Results in Scrapebox

Inspired by this thread here..and of course past experience with scrapebox I seem to sometimes have no results or very little.

http://www.blackhatworld.com/blackh...nts-what-they-really-how-get-create-them.html


I do custom footprint inspired by the above post. I receive 0 results with scrapebox. If I search this with google get ~7.8 million results?

I am using public proxies.. likely the culprit?