I am trying to capture text blocks which start with the header “Sender:” or “From:” and contain the keyword “SOA”.
The original text is

start of original text

Sender:
John Doe
This is an email about Service-Oriented Architecture (SOaaA).
From:Jane Smith
body: This email is unrelated to SOA.
Sender:John Doe
body:none
Sender:Jenny
Let’s learn SOA!

end of original text

I expect to capture 2 groups as,

Group-1

From:Jane Smith
body: This email is unrelated to SOA.

Group-2

Sender:Jenny
Let’s learn SOA!

My trial

I tried (^(From:|Sender:)(([sS])SOA)?)(?!(From:|Sender:)) but cant’ have good result.
Any suggestions?
Thanks in advance!
Samuel