Your question is lacking a lot of details, but a possible approach could go like this:
If yes - you can just search that new index. If not, something has gone wrong with the input itself.
Hope that helps - if it does I'd be happy if you would upvote/accept this answer, so others could profit from it. 🙂
Thanks for your answer,
i'd done all what you have mentioned and i follow the tenable Splunk guide :
https://docs.tenable.com/other/Integration_Guide-Splunk.pdf
Moreover, all the scans in my Nessus scanner are not getting in my Splunk.
I'd be very thankful if you have an recommendation regarding this issue.