In order to exclude Ai or EPS files, kindly select only photos from the Filter option.
Once you type a keyword for your search, on the left top you see a filter option, kindly select photos and then click update.
This would not include Ai ot EPS files.
For more information or help, you may get in touch with Adobe support :
You may also refer the FAQ's :https://helpx.adobe.com/stock.html