This is a suggestion to organize the list of regular expressions into two columns (what it does when used in the “find” box) and (what it does when used in the “replace” box)
https://help.libreoffice.org/Common/List_of_Regular_Expressions
Also, why not add a hyperlink to this page in the Find/Replace window
Thanks 
@Horst, thanks. I forgot about that extension. I was going to include the ICU link, but it had few examples of use, so I decided against doing so.
It sounds to me more like a request to expand the list given under the Examples. This would certainly help users better understand how regular expressions work. LO uses the ICU regex engine and so it is important to be aware of what this engine supports and what the limitations are (Wikipedia). I highly recommend this guide for learning about regular expressions:
http://www.regular-expressions.info/quickstart.html
The indicated organisation into two columns is not entirely workable. It is OK for the Search for field (this is what most examples on the web show), but does not work for the Replace with field as this is contextual and less common e.g., most regular expressions, such as .*, will be interpreted literally (full stop followed by asterisk) in the Replace with field.