Formula checkbox & contains statement

I have a multi-select (lookup) field that contains several strings of text [Monthly Status Report - CLIN].  I have a second field that is a Text (lookup) field that has one string of text [CLIN].  I need a formula to check a checkbox if the text in [Monthly Status Report - CLIN] contains the text in [CLIN].  

***Side note:  The text in [CLIN] will only be part of the multiple strings of text found in [Monthly Status report - CLIN].  A real example is:  [Monthly Status Report - CLIN] contains 0001, 0002, 0003, 0004AA, 0005, 0006.  The text in [CLIN] contains 0001.  

If(Contains([Monthly Status Report - CLIN],[CLIN]),true)

But this formula is not checking the box.  Can someone please help me solve this problem?