I check my keyword rankings using rank checker and it appears that my rankings had gone, can somebody tell me what happen.? thanks
Hay give some information about your site then it will possible to say. And check whether you have done any on-page changes.
There are a lot of reasons. 1. How long have your website ranked for those keywords? 2. How old is your domain? 3. How many link popularity in Google? 4. How many pages of your website? 5. What is the past link building strategy you had applied? If you just say dropped without more info and given url here. I doubt if someone could help you anyway.
Google have been on a campaign to de-index sites they consider spam over the last month or so. They have primarily been targeting MFA sites, so if you had a site that was thin on content or had poor quality content there is a good chance that it was de-indexed.
As the poster adove stated. If you have crappy content the chances for deindexing or horrible bad rankings are high. Unique content for the win (Always)
It could be a number of different things it's really too hard too tell without knowing your website and what you have done to it.