Google Penalty for single keyword

[Fotis]

Hi to everyone,
I would like to say my story. (It's small, don't worry! )

So, i have a company website. At the past at [keyword1] i have a 30-40 position, and at [keyword1 keyword2] (phrase) i had 14-24 position for the same url (mysite.gr/url1).
At the start of the new year i decide to "promote" my site. I wrote 5 articles andi submit them at article directories, and i bought about 10-15 blog comments (manually supposed!) from fiverr.
My articles have anchor txt [keyword1] with link to my url.
After these actions, i ranked at 10th position for [keyword1] and at 9th for [keyword1 keyword2].

But, at 15-16 Jan my site dropped very much.
[keyword1] dissapeared at all.
[keyword1 keyword2] rank 38th position. (same url)
The keywords are very low competion keywords.
I know that at this period there is a google update.

The website is company, so i cannot add many content yet.

Also, at past before 1-2 years i had use an x-rumer service but no affect then.
Now i check the webmaster tools for my backlinks, it shows 491 backlinks. 255 for url that i have ban for the keyword1] and 230 at my homepage. About 100 of them are from i forum that i participate (nofollow), other 150 are dofollow from blogroll of my one blog <-- anchror texts "keyword1", the rest are from some directories and etc.

At webmastertools i have not recieve any message about penalty.

All the above are for the same url of my domain. (mydomain.tld/url1)

What do you suggest me? I am sure now that i have penalised for single keyword.
How can i recover? Start link building with many anchors texts and for all of the websits's urls? If i change the name of the url and make 301 redirection will help?

Sorry for my pure English.

[KernelPanic]

No, don't 301 the problems to a new site. Check your site for duplicate content; did you place the articles that 5er spammed all over the place on your site?

We are not talking about a lot of links, I would recommend some great links and awesome content to recover.

[htmlizer]

Redirect and a new page will not help. It may be a temporary penalty so I would recommend to wait for several weeks. If the keyword doesn't return try to put 1 or 2 high quality backlinks. And if this doesn't help, buy a new domain and try not to spam it.

[Fotis]

Hi, thanks for the replies.

No, don't 301 the problems to a new site. Check your site for duplicate content; did you place the articles that 5er spammed all over the place on your site?

We are not talking about a lot of links, I would recommend some great links and awesome content to recover.

i have not copy content from other site. (one other site coped my content (because he make a review of my products) but now i told him to diversify the text)

Redirect and a new page will not help. It may be a temporary penalty so I would recommend to wait for several weeks. If the keyword doesn't return try to put 1 or 2 high quality backlinks. And if this doesn't help, buy a new domain and try not to spam it.

I have some unique articles. Do you suggest to put them at articles directories (such as ezinearticles.com, etc) with links to all urls of my site? (i cannot post them at my site because these are at another language).