Our toilet would not flush poop and when we tried to plunge it it backed up and came out through our bathtub. We are on sewer and we had a plumber come over about 2 weeks ago due to our toilets always having to be plunged no matter if it was urine or poop. So the plumber said that he souped up our flushing and it flushes slightly better but we still have to plunge. Then today it will not plunge and it is backing up into our tub please help!!

I don't know how he souped up your flush, his time should have been spent rodding out the drain after the toilet and tub intersect. You have a blocked drain not a bad flush. Call a new plumber. One who carries a license.

You have a main sewer line or at least one the one from the bathroom stopped up, They need to take some sort of snake ( manual or electric) and clean out the pipes.