Search one file to see if it contains information from another file

Question

So I have two files. The first is unip.txt and the second is ipex.txt and each file contains IP addresses.

unip.txt                                            ipex.txt

49.235.113.205                                      51.15.134.103
50.115.166.136                                      148.70.23.131
51.15.70.104                                        151.141.0.0
51.15.87.74                                         97.89.32.238
51.15.134.103
146.148.13.9
148.70.23.131
148.72.212.161
148.216.29.46
149.56.141.193

I'm trying to figure out how to basically search the unip.txt file to see if it contains any IP from the ipex.txt file. I imagine that it would be a loop to search through every line but after searching online for a long time I can't find anything useful. Any help would be useful. I apologize for anything that makes no sense, english is my second language.