How can I filter/forward mails that contain a certain word

I want all mails that contain a specific word on the title to not appear in the unified inbox, already on arrival, because it gets cluttered, but instead in a specific folder. How can I do that?

Set up a corresponding rule on your server.

I set up all those mails to go to a specific label in Gmail. The problem is, they still appear in the unified inbox

Labels in Gmail are not the same as folders. The mails remain in your inbox and are thus correctly shown in your unified inbox.

There is a nice blog post about the issue by Tom Scott (however, there in relation to conversations, not just rules).

Ok I’ll look for it. However my problem remains.
Btw Thunderbird has that possibility and your soon the same?