Search Result returns Document Title instead of Filename
This is one of the know issues for Search in SharePoint ,if you have CU October or later installed on your servers.
Follow below steps to fix the issue:-
1.Go to Central Admin —> Manager Service Application —> Search Service Application.
2.On search administration page,click on Search Schema under Queries and results.
3.Click on Crawled properties and Search for the properties called Title.
4.Once you find the Title property, click on it and edit.
5.Scroll Down and go to mappings to crawled properties.Select the “MetadataExtractorTitle” and move it down to last place,Click OK.
6.Perform an index reset.Click on Index reset and select option to deactivate search alerts, Click OK.
7.After index reset.Click on Content Sources and start full crawl (in my case it was local SharePoint site).
8.Once Full Crawl is completed, Search result will return filename instead of document heading/title.