Hi,
Could you elaborate a bit on what you like to search where, because this is a bit confusing.
Try and create a reprex where you generate two or three data frames at the start that represent the files that have to be searched (or part of each file) and the one that is the excel file. Then show us what you like to count in each file and what the output should look like.
For example, if a string appears multiple times in one row in a file, but also in different rows in the same file, how should this be reported...
A reprex consists of the minimal code and data needed to recreate the issue you're having. You can find instructions how to build and share one here:
Good luck
PJ