Google tranlator:

Hi Bedrich H.

They are called special characters (called escape characters).
URLs cannot contain spaces. If you assign a url with a space, the browser will automatically add %20 to fill the space.
In this case the special or escape character "?" it means that from there the direction will change. What precedes that character is identical for the entire "block" in this case of the products. (see images)

In the first image, we assign the product name according to our language, including space.

As I mentioned above. The URL must not contain spaces, and in this case, website fills the space with the hyphen -
This prevents browsers from padding with %20, which gets confused if a number goes in any direction.

As you can see in image 2. The URL is divided into two, the first part with the identical address for the same related products. separated by the escape character ?
after this character we can change it for something much better in sight or that does not generate confusion.

In the highlighted line of Tag Title it is as it is in our language with spaces, but the URL is already with the rules established so that there are no spaces.

Here With another product... the first part of the URL is identical, and after the escape character ? we can modify with something that allows us to better read said url.

The same happens with the url of the blog that adds the ?

I hope that I have made myself understood, and that the translator does his job well.
Greetings. :)