You can optimize PDFs to help achieve better search results by following a couple of steps when preparing PDF files for publication:
Complete the document properties.
It seems like the vast majority of PDFs are without specified document properties, the most important of which is the Title. The Title property represents the words that will be displayed as the heading of the search result. It’s the equivalent of the html title tag.
If you don’t complete the Title property, the search engine is going to generate a title from the PDF’s content, and it may not be what you would choose. We’ve all seen some pretty goofy looking titles to search results associated with PDFs. Not only do they look ridiculous, but they probably won’t get clicked. In the full version of Acrobat, go to File>Document Properties to specify the Title.
There are other document properties (meta data) you can supply, including Author, Subject, and Keywords, but presently these appear to have little search-related affect.
Influence meta descriptions for PDFs
For web pages, the meta description is what is displayed under the title in a search result. With PDFs, the search engines search the copy of the PDF and select something to display. While with PDFs you have less control of what is displayed as the description to the search result, you can still influence this.
The best way to do this is to make sure that you have a good, optimized sentence or two near the start of your PDF. If these sentences correspond to the search term used, it’s likely that these sentences are the ones that will be displayed as the description under the search result’s heading.
