When searching in SharePoint 2013, you’ll might come up with some odd search results. You’ll notice that these are titles extracted from documents, or even just random words. This is because ‘MetadataExtractorTitle’ is set as number 1 priority in the managed property ‘Title’. The metadata extractor in the content processing pipeline extracts metadata from the content that you crawl. If you notice titles as ‘Insert here’ or ‘Excel’ and you’re not happy about it, you change this by going to Central Admin >> Search service Application >> Search Schema.
move the ‘MetadataExtractorTitle’ towards the lowermost order.
For this to work, you’ll need the October CU!