Formula to find text in cell with alt + enter

I have a column with data in the cells. Some of those cells have an alt+enter in between the text to visually display the text on multiple rows.
I have another column with data in the cells. In the third column I need a formula that will look in the first column for the text in the second. Caveat, the data in this second column might only be a subset of the data in the first column.
Example:
Cell A1 = This is to test a formula.
Let's see if it works.
Cell B1 = Let's see if it works.
Cell C1 = need formula here

Thanks.

Sorry about the incomplete request. Thanks for the help.