Yes, you are correct, such incidents as killing Jews by the Poles after war indeed occurred. As far as I'm concerned, there is one proper scientific study about this subject published, and it's a book called "After the Holocaust: Polish-Jewish Conflict in the Wake of World War II" by Dr Marek Jan Chodakiewicz, historian of University of Virginia. It's a number of researches the author conducted, based on which he estimates, that between 1944-1947, from 253-615 Jews were killed in Poland. The motives were various, the most common were: antisemitism, robbery, false perception of danger (stranger in the village could've been seen as NKVD officer, etc.). Therefore, in many cases, the reason for murder was not outright hatred for Jews. Although, there is absolutely no denying, that it's despicable that such incidents occured. According to Chodakiewicz, in the same period, between 258 to 580 Poles were killed by the Jews, also for various reasons. Book contains for example a description of a case, where Jewish woman (out of gratitude for ending the war) turned over an entire group of local Polish underground resistance to the Soviets. They all ended up in gulag, including a person, who gave this woman a shelter for three years during the war. However you don't see me claiming, that "after war, Jews murdered Poles, no Nazi/Soviets making them to do so". It simply shows, that every nation has it's criminals and degenerates, which shouldn't be so much of a surprise. Also, the war (let alone, the biggest conflict in human history) reveals the worst instincts in some. Disrespect for human life and property rights are some of them, as Chaim A. Kaplan, to which I reffered earlier, also said. The thesis, that Poles - as a nation in general - murdered Jews, is simply not true and in order come up with it, you need to completely ignore all the facts I've mentioned earlier, plus everything else that is known about this period.
And by the way, the property that belonged to Jews (and all victims for that matter), was confiscated by (firstly) Third Reich and later by the Communist State. Those who survived, could've reclaimed it after the war. The rest of the property was sold by the communist government to those, who wanted to buy it.
As for Kielce Pogrom, there is also completely no denying, that what happened, was outrageous. However, like in every criminal case, you have to look at the context of the incident. First of all, it doesn't make too much sense, that it was done by the civilians. Nothing like it happened before nor after. Second of all, it's well documented, that the communist militia was there at the time and actually started the riots by opening fire. There's a handful of proof, that it was conducted entirely by militia, communist secret police and some criminal Polish element. To understand, why would they do it, you have to look at Polands' political situation at the time.
In the internal politics of the Polish People’s Republic, it was also a matter of drawing public attention away from the falsified results of a national referendum, which had taken place only two days earlier: on June 30, 1946. Despite the communist propaganda calling on the population to vote “Thrice Yes,” Poles voted “No” all three times. The pogrom and the authorities’ reaction to it drew attention away from this manipulated referendum. They also drew the world’s attention away from the issue of the Katyń Forest Massacre, which was being reviewed by the Nuremberg War Tribunals at the time. In 1946, Roman Andrzejewicz Rudenko, the lead prosecutor of the USSR during the Nuremberg Trials (later, he became the Prosecutor General of the USSR) presented the indictment concerning the murder of around 11,000 Polish army officers in Katyń by the Third Reich. Because the trial was not proceeding exactly as the USSR would have liked it to, it was necessary to draw the public’s attention away by using a subject about which the world was very sensitive at the time. And so, on July 4, 1946, when the material evidence concerning the Katyń Forest Massacre was being presented to the International Military Tribunal in Nuremberg, the trial began to proceed in a direction inimical to Soviet interests. Stalin was well aware that this would happen, and so he needed an event to take place which would effectively take the public’s attention away from both of these subjects, which were equally uncomfortable for him. The pogrom fit perfectly. The date of July 4th, agreed upon by the then-ambassador to Poland, Bliss Lane, was specially chosen so that reports of this event would reach American audiences, and particularly, Jewish-American audiences, as soon as possible. July 4th is, of course, American Independence Day: a day off from work, during which people aren’t occupied by the daily rat race. In 1946, this day happened to fall on a Thursday, and so publishing reports about the pogrom would occupy the American audience’s attention for much longer than a few hours. And so, once again, the pogrom played right into Stalin’s hands.http://www.doomedsoldiers.com/kielce-pogrom-the-truth-about-the-kielce-pogrom-comes-to-light.htmlBasically, Stalin desperately needed to create an incident, after which Poles would loose their sympathy in the eyes of allies, so he could take over the country, and proceed to torture and murder the rest of Polish elites, soldiers and officers in mock trials. It is estimated, that around 100 000 people were murdered, most of the times their bodies were buried in communal ditches, locations of most of which are unrevieled to this day. There was a case, where communists built public toilets in place, that later was found out to be one of those graves. It took 50 years to learn the truth about Katyn Massacre. It might take more to learn the truth about other incidents. Though, it will be difficult, since most of the files (including those regarding Kielce Pogrom), were burned by communists around 1990.
And for the record, I would like to highlight once more, that what happened during Kielce Pogrom was a tragedy and indeed, there is no discussion, that some Poles took part in it. Yet then again, example of Koniuchy and Naliboki massacre shows, that war revelied worst instincts in some people, regardless of which nation they belonged to:
https://en.wikipedia.org/wiki/Koniuchy_massacre