Import Tool Override existing Posts/Pages

I exported an xml of all posts and pages. However, I had to restore the database with an older sql file. (i.e. SQL backup file created October, XML file created December) When I restored the database with SQL file, I imported the more current XML file, but it will not override some of the page and post content. The pages and posts have October content even though I imported December xml. How can I override specific sections or ALL pages/posts with the import?