I have original in detail blog posts related to blogging and SEO. This domain has been dropped (expired) 2 times before my acquisition. I am the 3rd owner of the domain since 143 days.

Blog posts are not ranking even for exact titles. Google+ or LinkedIn shares will show up instead of my content.Some blog posts are not even indexed.

I am hardly getting around 7 organic visits / day.

Example 1 : http://www.infoflame.com/offer-pdf-of-blog-posts-for-likes-and-shares/    Title: Offer Readers PDF of Blog Posts for Their Likes and Shares not indexed at all. 

Example 2 : http://www.infoflame.com/anchor-text-for-seo/    is indexed but not coming up for the exact title.

Suspect: Dropped domain, less likely used for spam( WayBack machine (2 drops) 3 captures since 2004, I don't know whether there was Email spam) (But no manual actions in WMT, so no reconsideration request).

What's the reason for this? Should I wait? How can I tell Google that ownership is changed and the domain is now spam-free? or should I de-index it and start a new blog?

Thank you, for any advises.