Indeed, I guess it's a mental thing to thoroughly find the words to explain something? I'm not sure maybe it's just overthinking something. I hope someone has an explanation

I have the same problem which is why I prefer typing.
I tend to avoid spoken debates because I can't articulate my thoughts very well in speech.
But the only way to get better at it is by doing it, like most things.
Eventually your vocabulary will diversify and the words you need will just pop into your head when you need them. Ask any famous public speaker if they've always been good at it and the majority will say that they started out horrendously.

Yes, I experience it, but around people who don't understand me. You will find throughout life many great friends who will understand how you think, it's just a matter of finding these great people.