Keep trying!
In the meantime, I think you'll need to be adding the likes of
to your include element of the FILTER function.
Where exactly and whether you use multiply or add depends on which results you want to see.




For
you could use
although if there are errant spaces in those cells the liberal use of TRIM should help.




For you could wrap the whole formula in
All in all, quite convoluted.


Edit:
I note in your formula in msg#1 you have:
ISNUMBER(SEARCH (J2,R26:R500))
where there's a space between the H of SEARCH and the open parentheses. I hope it's the website's mangling of your formula because when I pasted the formula into a cell it didn't throw any error but the result was wrong.