Let's see how difficult it is to insert something from my Google Drive...
You can add a link to your Google stuff -
Google Doc showing correct hand placement (Google Drive stuff needs to be added as a link-the share settings must be changed to "Anyone with a Link Can View")

Pictures need to be uploaded from the computer or inserted using a URL. There is no SEARCH function when inserting an image. You have to upload or already have searched for the image on Google and copied the URL for that image.

Google Drawings can be inserted (see Cal. Regions pic) by first going to FILE and clicking "Publish To the Web"...then copying the EMBED code. Before inserting the embed code, first click "HTML" at the top left of your post page, then insert the code. Click preview to see what it looks like.
A Google Presentation can be added the same way as a Google Drawing.
Click HERE to watch a video of the steps to insert a Google Presentation into your blog.