I've found a more reliable method (at least on Excel 2016 for Mac) is:
Assuming your long list is in column A, and the list of things to be removed from this is in column B, then paste this into all the rows of column C:
= IF(COUNTIF($B$2:$B$99999,A2)>0,"Delete","Keep")
Then just sort the list by column C to find what you have to delete.