I don't known why I got out of SERPs for 1 keyword where I am was ranking very high (#1-#3 ) for months! However for the rests of keywords I am still high . Could this be possible if somebody reported my website for bad content etc ( I had to change my hosting company, so I uploaded my website to anather server)
Not necessarily somebody reported your site but, it could be something happened during the host change. Also it is very important keep in mind that you do not necessarily will remain in no. 1 for the duration of your website. Many websites compete for each keyword therfore, if you can not keep up with your competitors you will lose.
Well actualy, i even get more backlinks to me this friday ... and I am sitll ranking very high ofr others keywords as well... and this is not all , I am still ranking very high on msn.ca or msn.co.uk ,etc