Change Multiple Hyperlinks in Microsoft Word

Yes, you can use find and replace, even if your hyperlinks are underlying other text. Just hit Alt+F9 or Tools Options, View tab, and check Field Codes. This turns on viewing of the underlying hyperlinks.

Before viewing field codes:

After viewing field codes:

Now you can do a find and replace.

But what if you only see this and you need to change the web site?

Then just go to File Properties and change the hyperlink base.