Hi,
Did you configure the crawl rules? If yes, please remove them and have a try.
Please try to run configuration wizards in CA.
Also, you could try to do a full crawl using PowerShell.
http://blogs.technet.com/b/heyscriptingguy/archive/2010/09/28/how-to-use-sharepoint-2010-windows-powershell-cmdlets-to-manage-search-crawls.aspx
Please create a new search service application and test whether the issue occurs. If there is no issue, you could use the new search service application.
About how to create and configure a new search service application for your reference:
https://technet.microsoft.com/en-us/library/Gg502597.aspx
It would be better for us to find the root reason why full crawl didnt respond if you provide corresponding logs in ULS log.
An even better way to get the real SharePoint error from the ULS logs:
http://habaneroconsulting.com/insights/An-Even-Better-Way-to-Get-the-Real-SharePoint-Error#.VT7uonkcQ5d
Thanks,
Dean Wang