On QVP you can assign a tag to a media in order to help find it by searching for the keyword.
In order to assign a tag, you click on a desired media on QVP to open the media details. Under the general properties you can write a keyword or term in the tags bar as illustrated below.
As you can see in this example , 3 keywords are assigned to a media. This allows you to find the media by searching for any of the keywords assigned to it in the tag search bar. The tag search bar shows up by clicking in the main search bar on QVP.