Remove two new lines with one

How do you remove multiple ‘new line’ - \n\n with a single one. Same question on tabs. I have a large non fiction document that I need to format. Any help would be appreciated.

Unfortunately, the Windows version doesn’t have a way to insert newline or tab characters into the search fields. You’ll have to do that in a word processor, either before you import the document into Scrivener, or after you compile it to a word processor-compatible document type.