Searching for a day in search bar

I can find data in the primäry view about the search bar. But if I want to search a Special day it does´t work. If I enter one or two numbers it still works, but as soon as I enter the point as a separator between day and month the search remains blank. Number with Point in Question marks doesn´t work. The column have typ DateTime.
Hope someone can help me.

With best reguards