The search engines are not people. Search engines are simply software that visits your site. Search engine “spiders” look at the following
1) They check the last date you posted on your blog. If it is older than two weeks you will receive a lower ranking on their particular data base.  There are thousands of search engines that visit your site each month in no particular order. They visit one at a time. Keep your blog post up to date.
2) The TITLE of the blog post is the most important thing the search engines look at (it must have key words that folks would be looking for). If it does not have specific key words you are simply “not given a high ranking ..they move on.” Sites that have good key words in their page headings and post regularly get the higher ranking.
3) The pages of your actual site are scanned to see the HEADINGS of your pages such as each paragraph heading. Make your own changes and save thousands of dollars that might be spent on having an outside source do this for you.  Be careful because there are some companies out there that are not legitimate.  Learn to become your own webmaster and master your destiny!