As a general rule, nothing picked up by a microphone from a loudspeaker is actually going to sound much like the "real world" version when heard through the cinema or TV sound system.
As David says, you generally get the best results by making a "clean" recording of the person speaking with a high quality boom or body-worn microphone, and simultaneously making an "ambient" recording of the same audio coming out of the loudspeaker, capturing the room reverberation and so on.
Mixing those together in Post will then give an on-screen rendition which sounds much more convincing.
The same principle applies with rock concerts and similar situations. An audio feed from an on-camera microphone mixed with "clean" feed from the mixing desk gives pretty convincing results; neither signal on its own sounds any good.
I can't emphasize enough the importance of good sound in your productions. Good sound is often what makes all the difference between an amateurish production, and one that looks like it might have been done by professionals using amateur equipment.