I’m trying to show an average ‘trophy’ for some country that has more than 20 trophies – how do I do that?

This is my code

select 
    country, avg(trophy)
from 
    (select country, club from Tbl_Club1
     union all
     select country, club from Tbl_Club2) as country
join 
    Tbl_Trophy tr on country.club = tr.club
group by 
    country

And this is the result of this code:

result

Basically, I just want to show Italy and Spain only, because they have more than 20 average trophy