Hello Emil,
It sounds as if you might be dealing with the after effects of the hacking on your website. We dealt with a similar situation with a client of ours last month who saw similar effects after his site was hacked. From that experience, there are a couple of options:
- There is negative SEO being performed on your website
This would require a link audit to determine whether there are significant negative linking practices being performed on your website. This might also account for the penalties you are suffering (depends on whether you're getting hit by Panda or Penguin). Once this audit is conducted, a good SEO should be able to determine where the issues are and suggest future security actions to avoid it being repeated.
- There are still active hacks on the website
This is a job for a more security-oriented person. SEO's can general diagnose these problems, but solving them requires a complete site audit to determine whether code has been hidden on your site. I have a team member who solved the problem this way - it is a tedious and time-consuming process, but it is better to solve the problem completely than be hit over and over.
- Re-consideration request
Given you have been hit by multiple manual penalties, you will have to submit a reconsideration request with Google. Make sure you have solved all of the above problems before you send that, or you might never recover the site. A client of ours was in this position, and it took them about 2 years to recover fully.
Sorry to be the bearer of bad news, but please feel free to reach out to me and I can give you some further tips and tricks to help with solving this issue.
Hope you can work it out and that this helps a bit!
Best regards,
Rob