Excel count how many times a value appears in a range looking within cells

I have a column with unique emails and I need to count how many times each one is in another range with emails BUT in this one the cells can contain more than one email, and they are separated by a blank space, is there a way to count them?

Thank you

>Solution :

Try the following it will give you the exact number of occurrences as per your screenshots:

=LET(
     _Instances, SEQUENCE(,MAX(LEN(AllEmailsList[AllEmail])-LEN(SUBSTITUTE(AllEmailsList[AllEmail]," ",))+1)),
     SUM(N(IFNA(TEXTSPLIT(TEXTAFTER(" "&AllEmailsList[AllEmail]," ",_Instances)," "),"")=[@[Unique Email]])))

Another alternative way using FIND() & COUNT()

=COUNT(FIND(" "&[@[Unique Email]]&" "," "&AllEmailsList[AllEmail]&" "))