I\'m not very expert to PHP. I want to know how to communicate between 2 web servers. For clearance, (from 1st Server) run a function (querying) on remote server. And return
What you are aiming to do is definitely possible. You will need to set up some sort of api in order for server one to make a request to server 2.
I suggest you read up on SOAP and REST api
http://www.netmagazine.com/tutorials/make-your-own-soap-api
Generally you will use something like CURL to contact server 2 from server 1.
Google curl and you should quickly get idea.
Its not going to be easy to give you a complete solution so I hope this nudge in the right direction is helpful.