Translation of restringir

I would rather like that you write through the messaging system on this site and not to my private email address. All the info is gathered here online and I would like to keep is this way. It is nothing personal.
It is good if you have previously practiced only Spanish, which also shows that you are very good at other languages, and still can learn many things. I hope I'll learn it soon and practice.
I have learned German for one year and I would like to intensify my studies. Do not know how yet... It is very difficult at my age to start new projects in life. I am over 75, did I tell ya...