Need to compare strings for case sensitivity

I need to compare 2 strings using a pattern and i need the compare to be case sensitive.

CP is not case sensitive

CA is case sensitive - but it wont search for my specific pattern - it will find strings where any of the charaters match. I need to match on the whole search string.

Example: searching all long text fields that contain pattern Rm167.

my results are returning rm167, RM167 and Rm167.

How do i find ONLY Rm167 ?

Please help,