The R's currently sit second from bottom in the table and have yet to find their first win of the season.
"In the last two days we had meetings, sat down and let individuals know in no uncertain terms it's unacceptable," Bowen said in QPR podcast Open All Rs.
"They held their hands up and took it on board and we will work at it to make sure we are better next time. We encouraged them to point a few fingers and put demands on them. I want them to be a bit more angry and demanding of each other."
QPR travel to the Britannia Stadium to take on Stoke City this weekend.