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.

Several faces can be captured on the sample for search. Click on the face for search to select it. 

As a result the search of the selected face will be performed.