How to detect desired collection of words scattered in multiple lines

Hi @Umer_Shahid ,
The file is probably corrupted somehow.
Anyway, here is the screenshot of the workflow. You can build your own from this one.

First, I took the whole text you mentioned in the post in a notepad and read that in the strInput String variable.
Then I have split the whole text with respect to the Uppercase word “INSTRUMENT” and put them into a List of String

strList = strInput.Replace(environment.NewLine,“”).ToUpper.Split(“INSTRUMENT”).ToList

Finally, I removed all other words and kept only the notice number and printed the desired output with String Concatenation for each item of the list.

“Notice Of Change of Address For Service-Instrument “+item.ToString.Trim.Replace(“NOTICE OF CHANGE OF”,””).Trim.Replace("ADDRESS FOR SERVICE- “,” ").trim

Hope this helps you.
Thanks