It's possible to upload an image from a file in two ways:

1. Click the Load image button and select the Load from file value in the opened list.
2. Double left-click on the area of image loading.
   
   

Standard window of files selection will open. Select the required file with image and click the Open button.

As a result an image from the selected file will display in the Sample for search field on the panel of specifying search conditions.