[Theme: Thesis] Structured Data errors, not sure how to fix them

I’m running Thesis 1.8.5 and I’m having the following errors in my structured data, according to Google Webmaster Tools:

Missing: updated
Missing: author

My website is http://www.therichteacher.com

I know how to edit my custom functions file, but everything I’ve found about fixing the problem refers to editing the single.php file, and I don’t know where that is in my theme or if I can even edit it.

Has anyone run into this problem and figured out a solution? My rich snippets in Google aren’t being updated, and I think it’s because of these errors.

Thanks for the help!
Jessica