The software/service is not perfect. For example, there is not an exact match between some of the text surrounding the keyword and what is actually on the audio or video. But the matches are good enough to provide one with a fair idea if the indicated segment may be something in which one may be interested in pursuing further.
If the keywords for which one has searched are in a given audio/video podcast, a list of sections of the audio/video will be generated with the keyword highlighted and which, when clicked upon, will take you right to the portion of the audio or video where the keyword appears and play it. If one wishes to subscribe to the podcast, then, one can do this and, if one wishes to download the podcast one can do that as well.
If you would like to try Podzinger out in relation to my podcast, Sufi Reflections, please free to do so by going to:
scroll down the page toward the bottom and enter your keyword search in the Pod Zinger box on the left-hand side. I think you will find it to be a very interesting experience ... both with respect to the Podzinger service as well as in relation to the Podcast itself.
If you wish to broaden your keyword search to any and all podcasts listed with Podzinger, just click on the Podzinger option rather than the Sufi Reflections option. The service is pretty amaZING.