Rather that typing a long sentence, enter something like 'document separator'. This will return all the articles with the words 'document' or the word 'separator' in the title or keyword list.
An error may occur in a network admin/service account where there are group policies implemented on the network accounts. The COM error you may see is: "Retrieving the COM class factory for component with CLSID {ID} failed due to the following error: 80070005 Access is denied" [open]