This issue mainly concerns the CorelDraw 9 version; after CorelDraw 11, there are convenient shortcuts available, so this problem basically doesn't exist anymore.
Method One: For versions of CorelDraw prior to version 10, you can solve it by using the "Freeze" function in the filters. Draw a completely black rectangle over the paragraph text, then open Filter -- Transparency -- 100%, and check "Freeze" and "Remove Surface." Apply the settings, then remove the text layer behind it, leaving only the curves.