I don't know if this is related to theme or something else.
I used All in One SEO. Everything was OK. I entered meta description text and in Google search page it was the same text.
Then I installed Yoast SEO and first post I published was indexed by Google as usually but words from links were in description on search page.
Post url: http://www.mydomain.com/my-first-post
Meta description in WordPress: This is my first post
Meta description in source: This is my first post
Description in Google search:
29. Sep 2012 - my first post This is my first post
Then I uninstalled SEO Yoast and installed SEO Ultimate and same thing happened. I didn't change anything in template. I believe it is not pluggin problem. Description in source is OK. Why Google takes word from link I really don't know.
Thank you in advanced for help.