By nature, the dialogue box for search and search & replace allows access to the basic functionality. By clicking on the "More>>" button in the bottom left hand corner, more advanced options are then made available.
I have recently published an anthology of short stories on Amazon and as I was preparing the source document to be uploaded, I discovered that I had manually inserted hard carriage returns between paragraphs and that when I published my manuscript, I ended up with two blank lines between paragraphs.
My first instinct was to go through my document and manually delete the extra paragraph marker between paragraphs, but fortunately, I'm a rather advanced user of Microsoft Word and I knew that there was a much easier way of using the search and replace to do this automatically for me.
It's important to understand that it is possible to see many of the basic formatting commands within a Microsoft Word document as special characters. To enable this feature, click on the typographical "paragraph" symbol immediately to the left of the list of styles available. Once you've clicked on this symbol, you'll see visual representations of some of the formatting symbols, such as where the author as pressed the Enter key to insert a hard carriage return. You'll see to this writing snippet that there are two paragraph symbols. Looking at this sample, I realized that what I wanted to do was to essentially replace two consecutive hard carriage returns with one, effectively deleting the second one which was the blank line between paragraphs.
In order to do this, I first of all saved my document in case I made a mistake with my search and replace, then clicked on Search and Replace, followed by the More>> button to expand the dialog box. I then clicked beside "Find What" and instead of typing in the character string that I wanted Word to look for, I clicked on the "Special" push button on the bottom and from the popup menu, I selected "Paragraph Mark". This resulted in a ^p being inserted in the "Find What" dialog entry. I repeated this a second time as I wanted to search for two consecutive paragraph marks. Once this was complete, I ended up with ^p^p in the "Find What". Next, I clicked on the "Replace With" entry field and then repeated "Special" followed by "Paragraph Mark" but did not repeat it a second time. The result of these steps was the following dialog box as per below. Finally, when I clicked on "Replace" or "Replace All", all occurrences of two consecutive paragraph marks were replaced with one - effectively deleting the blank line between paragraphs.