Google does not index individual posts

Hello there,

I’ve run into a major problem with my website http://www.sauliusspurga.lt . Google used to index posts on my website regularly, but suddenly it stopped doing it. Now whenever I type a title of any post in my website in Google Search, it does not find that particular post on my website, it only finds it mentioned in the archives of my site. What happened? Why would Google not index my individual posts and display it in the seacrh results?

I am looking forward to your answers.