Yes it is. Provided you are following ethical means. If you are
following the proper ways and means, you will be able to manipulate
the search engine results.
Basically this manipulation will happen by itself, as you
improve the content, web design, visibility and such other factors
of a website.
The process used to manipulate search engine results is called
search engine optimization, SEO for short. This entails various
different methods and techniques which can be used to gain better
raking on search engine's.
However within SEO there are some techniques which are frowned
upon by search engine's and the SEO community in general, these
techniques are deemed as unethical and are termed as 'Black Hat SEO
techniques'.
'White Hat SEO' is the term used to describe the techniques
which are deemed as ethical. These can and are followed by leading
SEO practitioners across the world to gain better search engine
ranking.