Need Some Advice - Organic Rankings

[d5industries]

Hello everyone. This is my first post on this forum. I'd like to give you a 30,000 ft view of my
situation and then ask some specific questions.

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I started my website in 2012 as an eCommerce store. Overhead, shipping, etc.. became too much
hassle, so about 6 months ago we decided to migrate the site towards being more of a
"review and comparison" type blog. We provide in depth reviews, comparisons of similar products,
answer specific questions in our niche and provide "15 Best" style lists.

I have about 30 articles written so far ranging in length from 1000-3500 words each
(most are around 1500+ words).

My dilemma is this...certain articles seem to be ranking fairly easy (within the top 3-4) while others
can't crаck the top 50. These are for keywords that are fairly even in terms of competitiveness
and against the same grouping of competitors.

***Here is where I'm really stumped. I have a post that I've written to address "XYZ question"
I've included some form of the keyword in Title and H1 Tags. The post is written naturally, but the
keyword is nicely spread throughout main content. I have images that are tagged with various
keywords that "relate to" or ARE the keywords mentioned in the search query.

I have other blog posts that rank in the top 10 for the same query above because Google is picking
up the title of my article above in the "Recent Posts" section. These posts have nothing to do with
the search query above. Why in the world wouldn't Google pull the actual blog post which the
main content answers the above search query? The posts don't really have any difference in terms
of backlinks or internal linking.

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If this is in the wrong section, please let me know and thanks in advance.