You can't do direct backup/restore from database to other database with MS SQL Server...

Then you select "From database" in database restore options it doesn't mean what selected database will be used as source for restoration. In this case SQL Server Management studio perform a query among the msdb (backup history) to find databases that have been backed up. And last backup file of database selected (D:\Program Files\MicrosoftSQLServer(Exp)\MSSQL.1\MSSQL\Backup\test1.bak in your case) will be used as backup source.

You can't do direct backup/restore from database to other database with MS SQL Server...

Then you select "From database" in database restore options it doesn't mean what selected database will be used as source for restoration. In this case SQL Server Management studio perform a query among the msdb (backup history) to find databases that have been backed up. And last backup file of database selected (D:\Program Files\MicrosoftSQLServer(Exp)\MSSQL.1\MSSQL\Backup\test1.bak in your case) will be used as restore source.