[Search] Show results only that have tags that are equal to the input.

Dear Community,

I’m currently struggling with a method I wanna use on my website.
I want my visitors to be able to type a couple of letters or words in to a search box, but the thing is. I only want to show posts that have the exact same tag name.. Let say the search input is “50” and there are two posts with tags called “50”. I want to make sure the two posts are the only results that are shown.

Now it shows everything with 50 in it.. Even if i have some different content page that has 50 written in it.

I have looked for some plugins but couldn’t find any that was matching the requierments.

Any one have an idea of a plugin or code i should write?