You can try DeepMiner. It is good for scrapping, rank position, generating long tails and keyword suggestions. You can export the data to document for later analytics. You can find popular keywords that people are searching for. 7 major engines are supported, Google, Yahoo, AOL, Amazon, YouTube, Ask, Bing. It supports multi-threading so it is very very fast scrapper. BTW you must use proxy list if you plan to scrap thousands and thousands of keywords.
Basically, Google shows the autocomplete suggestions whenever you start typing anything into Google search box. It is in Google's best interest to show the most relevant keywords in the autocomplete suggestions. Keywords that would help Google to retrieve the most relevant websites and help users find the most relevant content for their search query.
Let me show you an example. I just surfed over to a very popular blog called The Busy Budgeter (www.busybudgeter.com) to find an example topic. Rosemarie is the blogger over there and I’ve been following her journey recently. She’s absolutely killing it online! But, I happen to know that she gets most of her traffic from Pinterest and that working on SEO is one objective that she wishes to tackle. So, let’s see if we can help her out… A quick scan of her homepage tells me what type of content she produces and who her audience is. It appears her audience is largely female, lots of stay-at-home moms and a good portion of her content revolves around teaching others how to make money online.
The limit on manual keywords could be higher.  I personally wish we could input 10,000 keywords at a time, instead of 200.  However, I understand the costs that Long Tail Pro has to maintain each time a new manual keyword is input.  Not a deal breaker, I just wish the limit was higher. (To be fair, I don't think most keyword tools have a bulk manual option at all).
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