SharePoint 2013: Importing a site, list or document library
Importing a site, list, or document library in SharePoint 2013
You can use Windows Power Shell to manually import a site, list, or document library. To import a site, list or document library by using Windows Power Shell
On the Start menu, click All Programs, click Microsoft SharePoint 2013 Products, and then click SharePoint 2013 Management Shell. At the Power Shell command prompt, type the following command:
Import-SPWeb -Identity <SiteURL> -Path <ExportFileName> [-Force] [-NoFileCompression] [-Verbose]
Where:
<SiteURL> is the URL for the site that you are importing to.
<ExportFileName> is the name of the file that you are exporting.
See more at: http://expertsharepoint.blogspot.de/2014/01/importing-site-list-or-document-library.html
Note: I resolved the issue by above Method. If you find a different solution, please report it as a comment to this post. This will be useful to SharePoint Community. Be sure to double-verify it: undo your solution and verify that the problem comes back, then redo it and verify that the problem goes away.