Virtuemart search engine does not recognize punctuation marks (- , .)

[kernel]

Hi all!!

I am helping a friend to optimize a shop in VM2. The fact is that we have realized that the virtuemart search engine does not recognize punctuation marks like "- , : ;". For example, if I search the reference "12-abced.ee", in the virtuemart search page appears this "12abcedee". The punctuation marks desappear.

Is there any solution for this?

Thank you very much.
Greetings.

P.D.: The website is this: www.electronicajamer.es.

I edit this post to add some images of what happens:
1.- In the shop exist this product:


2.- But if a customer wants to find the product for the reference:


3.- The virtuemart search engine will not display any product because it has deleted punctuation marks:

[kernel]

I edited the above message including three images (for if useful).