Recently In our sharepoint portal when we tried to Search current site “This Site” from drop down we are ending up with 0 results always, however when we search same Query in “All Sites” we are able to get results.
I spent sometime investigating to see what the problem was by first going to the SharePoint Central Admin to make sure the search service application was started successfully including all the services related to SharePoint search in the Administrative Tools > Services.
It all look good to me. Also checked the search service application again do make sure the server had Full Search crawl successfully.
But what I also notice is when i looked at the URL of the page that displays the result which is theis that it was both used when i perform a search in the site collection which wasn’t working for Search “This site” as well as Search web part.
After some time searched over couple of blogs and found that the issue might be because of alternative mapping access , if the default zoned URL configured in alternative mapping access is mismatched between the url given on Search Configuration to crawl the data, we will face this issue .
So immediately i changed and make sure that both Alternative Mapping access Default Zone URL and SharePoint Search Configuration URL are same , then we can able to get the results .
Below is Microsoft Blog which has given in depth analysis why we need to use same url for both the things