Condition and Search string together not working

[satyajit2007]

In Total_error Count , I want to add if the logs contains string like "exception", "failed", "error" ( Case Insensitive if possible ).  in addition to level=ERROR condition. 

index=myIndex sourcetype=mySourceType | 
timechart count as total_logs count(eval(level="INFO")) as total_info count(eval(level="WARN")) as total_warn count(eval(level="ERROR")  ) as total_error span=1h

Added those search criteria like this . did not work . 

count(eval(level="ERROR" OR ("Failed" OR "Exception" OR "Fatal")  )

The condition should be 

where level="ERROR" OR ( log like '%failed%' or log like '%Exception%')    ( case should not matter). 

Need your expert advise.

[richgalloway]

I replied to your previous message on this topic.  https://community.splunk.com/t5/Splunk-Search/Search-strings-and-conditions-together/m-p/529223/high...