Yes! Once you search for something and are on the search page, you will see drop down menus for various parameters you can set including Author. You can also select the "Advanced" button to the right to expand the search options even further. This allows you to search for all posts by a specific author.
Hmm that's odd, I just tried the same search as you and got 377 results. Did you type a specific term or anything in the box? I am not sure what would cause our results to differ so much. Might have to have @KatieKing look into this.
If you are able to get a different result, definitely there are different input/options selected.
I will try to do a search again.
Please don't bother Katie King yet
To give a little background, I started off with the profile page of a user, say MLombard, looking for his blogs (just the blogs) under the first section 'Latest Posts'.
This lists just about everything though - forum questions, replies, blogs, blog comments, knowledge articles.
Hence my first post.
@AmyReyes showed me the way - advanced search - which I was not aware of or simply overlooked.
Even after that I was perhaps using some wrong parameters or missing something in the search which gave me just 24 results instead of the 377 you got so I am going to try it again.
... and here's the result. The list is all grayed out. I am not able to pick the blog item in the list, even after typing in some text 'Solid' in the text field and choosing a location and an author. I can post a screen-recording if you'd like.
Can you share a screen capture of the your search page showing the parameters you chose.