How do I do a search on previous topics

So, for example, I have this bookmark for the old forum, and it’s broken.

https://forum.classiccougarcommunity.com/viewtopic.php?f=39&t=12476

T=12476 would have been the topic ID, which would pull up the post on the old forum. But that topic ID# doesn’t take me to the right post on the new forum.

Fortunately, my bookmark name includes the name of the original post / topic: “wondering if it still exists”. So if I do a forum search for that topic name I get the following hit…

https://forum.classiccougarcommunity.com/t/wondering-if-it-still-exists/12112

The topic ID# is now 12112 for that same topic.

But I can’t just paste the old topic ID number into a link for the new forum to get to the same post as before. I have to know the name and do a search in order to find the old posts I have bookmarked.

https://forum.classiccougarcommunity.com/t/12112
^^Using just the new topic ID works and gets me to the right post.

https://forum.classiccougarcommunity.com/t/12476
^^ Using the OLD topic ID takes me to the wrong place ~ and in many cases does work at all!