SQL Query language problem

Ok, I am trying to figure out how to pull a query that includes all data from several different databases.

Here is the language I have written so far:

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The problem is, it is only pulling records that exist in all three databases. When I yank out the last month, it adds more records than previous. When I pull only the first month's records, it gives even more records from the July database than it did pulling all three months.

I do not know how to write the language to tell it to pull ALL data, regardless if whether it exists in the other months. I presume I am missing something or did something wrong so I was wondering if someone would help educating me.