This must not be very accurate. I typed mine in and no results came up when there should be quite a few. I think it would be more accurate to go to your local county sheriff web site for better results.
http://www.dps.state.al.us/public/abi/system/so/
I found several near me that the posted site doesn't have.
I tested it for myself. I had one with a background of similar arrests. Others tested it today as well bringing up many offenders. Zips in parts of Chicagoland burbs brought over 50. California also had some higher counts.
Perhaps yours are not on record?
I did the Test with several others in different parts of the country before I posted.
Zip Code search is NOT available for the following States: Oklahoma, Nebraska, New Jersey, South Dakota, Utah, Vermont, West Virginia, and Wisconsin.
None came up but my daughter paid $20 for the national list thru John Welsh.....and 48 names with pictures came up. They update the list every month by email.