Combine is so convenient?

Hi All

this is my 3rd building combination, but it seems this is not really convenient.

In these days I made one Golf Course, one Entertainment Zone and one Police Academy, but what I noticed is that every time I made a combination, my education went down and the rewards never increased as it supposed.

So what to combine building if this is the result?

Another question, how it is possible to get workers with education instead simple workers?

Right now all my immigrants was trained into workers and to get some workers with education it is not clear how to get them.