Excel Formula

Hello,
I am working on a spreadsheet and dealing with cells that don't just have the date in them they also have other information in the same cell. I am trying to write a formula to compare the date in the cell (remember the cell has text too) to the current date. I want to find if it is less than or equal to 6 months from the current date. This is where I'm stuck

=COUNTIF($C3:$IV65536,DATEVALUE("*??/??/??*")<NOW())

This is probably completely wrong. Can anyone please help?!