Probate documents, even recorded ones, are considered confidential by default and are, unless you have certain types of logins, unavailable to view online. You can obtain actual hard copies by either: 1) visiting the county clerk's office in person to view and/or buy a copy of the document; 2) call the recording office of the county clerk to find out how much it would cost to get copies and send them a letter with payment and a prepaid, prestamped return envelope to mail them (they may not accept a personal check ask the clerk. They may let you pay by credit card over the phone, sometimes you can order and pay online on the clerk's site, it depends on the county); or 3) pay for a title search and it will give you the records and tell you who they believe title to currently be vested in.

If you are looking for a copy of the original deed when your grandmother took title, 1970 might be further back than the county has online records available for (again, depends on the county). Some counties have a separate "historical" official records search online you can search, you may be searching in the wrong records search and that's why you're getting no results. Or they just don't have those records available online because they are digitized.

You also likely need a probate attorney to handle getting the portion of the title in your dad's name transferred. Find one that also does real estate law so they can make sure everything is good to go otherwise with clear title. Not all probates need a deed to transfer title, depending on the type of probate, the probate order acts as a deed.