Google Scholar provides a basic search for scholarly literature across many different disciplines. It will attempt to focus on scholarly research, not just general information on the Web.
Not everything in Google Scholar is free, but it can help identify what is freely available.
Google Scholar will not show everything in the ACU Library databases, so it is not a substitute for searching the Library. If Google Scholar finds something that would normally cost money to access but that is available to you free at ACU, then it can link to ACU so you don't have to pay.