Hi peek201,
We appreciate you reaching out to us. We understand that you are experiencing issues searching for calendar events on your iPhone.
We’d like to gather additional details that may help us be in a better position to assist you.
Did you use the steps in the article below to set up your Calendar?
Set up iCloud for Calendar on all your devices
If yes, we recommend that you check for a software update.
While it isn't inherently assured that an update will resolve the issue, updating to the latest software version for your device can help isolate potential software issues.
Kindly secure a backup and update.
How to back up your iPhone, iPad, and iPod touch
Update your iPhone, iPad, or iPod touch
If the issue persists, we recommend that you reach out to us here so we can take a closer look into the issue: Get Support
Take care!