Hi, thank you for your answer but I think this is not solving my problem - it is because i have only up to date norms in my Catalog, and there are many other older possibilities of those norms - and those are not listed in my Catalog but they can be found in my work documents...

For me I think the only solution is to design special conditions for finding these norms in document and than again finding and then replacing their equivalents from up-to-date Catalog- I have already made up these conditions to find- and select- the proper text string, now I am asking for help to do the rest of the programing because I am really beginner in that...I ll try to write these finding conditions here as soon as possible, so that you can maybe help me better. And thanks for your help, I really appreciate it a lot