This can be quite normal. Because Airbus Pleiades imagery is a very high resolution sensor and has a limited swath width, the constellation is unable to cover the same amount of area as Sentinel-2 does for instance.
Naturally, acquisitions are focussed on areas of the world that are more populated and potentially of interest to buyers of satellite imagery. So in your areas of interest there may not be any Pleiades imagery acquired in the last 6 months.
I also tried a search over a large area of Venezuela for Airbus Pleiades imagery for the las 6 months. As you can see, the image coverage of the AOI is very limited and mostly around urban areas.
If you are looking for more complete coverage you may want to either increase your time range, and to also search for images from other constellations such as Maxar and PlanetScope.