I have a strategy in mind to increase my site's SEO. Basically I want to position my site on the top few google results for a particular keyword. Eg: Toys. If I provide bloggers with unique articles, all related to Toys and ask them to set the same keywords in addition to providing a back link to my site. Will it be possible for me to increase my site's authority for the word Toys? In other words, If I can get 5000 blog articles to point to my site with the same key words, can I make it to the top of Google's search results if a user searches for Toys? Thanks in advance!
If you got 5000 sites to link to your site using the same keyword you'll likely be flagged for spam and attempting to manipulate the search results. That is an old-school attempt at SEOing a site that Google and the other search engines have already developed algorithmic answers to.
There are three aspects to building up your search rankings.
1) On-Site Optimization: Your site has to be coded in a way that is search and mobile friendly. You need to optimize your content for searcher's topical interest's (keywords), and give your visitors a great on-site experience by focusing on usability issues.
2) Content: You need to create and publish awesome content that fills the needs of the audience you're trying to reach. Write blog posts and create other forms of content that answer questions, provide tips, and map out solutions that truly illustrate that you are an authority on the topic.
3) Social Engagement / Links: Links are an important part of the algorithm, but getting a bunch of sites to link to you using keywords is the wrong approach. You need to be engaging on social media and (to a far lesser extent) socializing your content above. But the more you engage, the more others will socialize your content for you, which is where authority is really built.
I totally agree to Stoney deGeyter. 5000 backlinks sounds like spam. It's almost impossible to get so many good ones, except your Tim Cook ;-). Better focus on good contents and some high quality backlinks with real traffic. And don't buy any backlinks!
I think Stoney is on the right track here, but the only thing that's missing is that this question cannot be answered correctly without actually knowing the industry and current leaders. There are different industries and topics that Google has different tolerances for. If authority websites on your topic commonly have/receive lots of backlinks from bloggers, you have more room to play with in this area. Also, social media is not a requirement for SEO. We've seen plenty of sites outranking competitors with no social presence at all. There is no one formula for what SEO should look like across all industries. The only place I'd say you're definitely looking at raising a red flag is with the anchor text. In your example you said you'd want thousands of links back using the same keyword. Chances are, no matter what your topic or industry, that's going to look very out of the ordinary. A natural looking, balanced link portfolio is really key these days in offsite optimization. You'll get all sorts of people these days that tell you to "build content people love" and SEO just happens. That's not the case, especially in an industry with any competition at all. SEO is a deliberate, calculated marketing strategy. If you feel that you're in an industry that's even remotely competitive, then I'd recommend seeking out an SEO agency with a solid reputation. If you're bootstrapping a business and looking to do whatever you can on your own, then I'd start by educating yourself on SEO from reliable resources such as: https://moz.com/learn/seo. (I'm not affiliated with Moz in any way). Best of luck!
Why try to get "toys"? Why not a long-tail keyword? It's going to be impossible to get "toys". (Unless you are rewarded by Google for being local) You'll be competing with informational results like Wikipedia and queries like "what are toys".
Be specific. "Toys for children under five" or specific toys, balls, rattles. Long tails will have more of a buyer intent.
5000 links to toys, that's just silly.
Probably Not Mine answer because of some issue
Recently updates from google Anchor text most import topic on the eyes of google engineers,Anchor text Distribution is more important in Link Building May be your Site Ranked Some Time But Its not working Proper Because its lose your Visitors in Future
In addition to these good answers you are receiving from these other experts, I would like to add another consideration, and that is you would be wise to be careful in your selection of bloggers to approach. It is not about quantity but quality. You should research who are the bloggers who are key influencers in the subject(s) most related to your product or service. Then review their sites, policies, and media kits if they have one. Some bloggers accept guest posts, many do not, almost all will charge a fee for product reviews and sponsored posts. Do not contact any one blogger until you determine that he or she seems to be a good fit for your purposes. Then you will see if that blogger is interested in working with you. The generic approach is a poor strategy - bloggers are individuals and no two are exactly alike.