C206 pilot reported an NMAC with multiple gliders while in cruise in Class E airspace.

Narrative

During a IFR cross country flight from ZZZ1 direct ZZZ2; acting PIC and Co-pilot spotted traffic off of our 1 o'clock same altitude approximately 4-5NMs away. I (Co-Pilot) asked ZZZ Approach if they had traffic on radar. ZZZ approach responded that they did not. The PIC was planning a course deviation away from the traffic; however the traffic was circling. Due to the circling; This was making it difficult for the PIC to decide which way to alter our course. After a small delay; the PIC was forced to make an evasive action successfully away from the traffic. Upon closer examination; the traffic was identified as a glider. Multiple gliders were spotted a few minutes later around the same area.Approximately 10 minutes later; another glider was spotted at our 10 o'clock same altitude. I again radioed ZZZ approach asking for the traffic update. ZZZ approach was unable to locate the traffic on their end. This glider was also circling; creating a difficult decision on which way to alter our course. After a small delay; the PIC was forced to make another successful evasive action.