Custom harvester doesn't work

I am trying to make the custom harvester scrape only 10 urls per page because i am using advanced operators like this inurl:.edu/phpbb2 and i am trying to avoid google blocking my IP. But every time i start the harvester it scrapes 8 urls and stops.

This are screenshots from my settings:





This is google search query:

Any idea why the harvester doesn't want to scrape?