Here's a tip that will surprise you as much as I do! I would never have thought of it without watching the video!
Why cover the toilet bowl with plastic wrap? To unblock the toilet!
The Saran Wrap (or any other brand of plastic wrap) will create a suction effect that will unblock the toilet, for example.
Cover completely the bowl with the plastic wrap.
Flush: the plastic swells.
With both hands, press firmly on the plastic: the pressure will burst the plug in the pipeline!
Watch this short video.