https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.itemscontrol.istextsearchenabled?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0&redirectedfrom=MSDN
ItemsControl.IsTextSearchEnabled Property (System.Windows.Controls) | Microsoft Learn
Gets or sets a value that indicates whether TextSearch is enabled on the ItemsControl instance.
property systemwindowscontrolsmicrosoftlearn