Google custom search - poor image results

Question

I've created a Google Custom Search engine to add an image search functionality in my android app.
In the Google dashboard, I've added *.google.com as a website to search in with the aim of propose to the user the same image results he would have found on google from browser.

Below the complete configuration:

• keywords: empty
• edition: free, with ads
• image search: on
• speech input: off
• language: english
• sites to search: *.google.com
• restrictions: empty

The problem is that results are poor and very different from those from google.com.
How should I configure my engine?

Answer 1

The problem was a setting in Site to search section with the value search only included sites. I changed to entire web and the results are now similar with the browser version.