if google just search company .that company will last 4-5 yr. but google enter various industry.that company can go to 20 yr
As a search engine - Google will lost its dominance position on the market sooner or later, as an internet company it may exist about 20-30 years. Even the search professionals speak about the possible displacing of the Google. Here is an article concerning this topic - Google could be superseded by Semantic Web
Of course it will, they keep getting better and better. Already introduced semantic search engines that are twice as smarter as before. The search is not just based on backlinks and code, and god know what other technique seo "experts" think they are SO useful that spend 99% time on them, but on the content revelency also. They match your site with a perfect content they have in mind (that you should partially have), called ContentDNA. They are matching and ranking accordingly the site based on how much it matches. ContentDNA it's not just synonims of your search term, its the whole information from the internet that matches a certain environment's associations for this earch term (common neurolinguistic map), therefor if human's brain associate sport cars to ferrari or porsche, and if your site is about sport cars, you will HAVE TO include ferrari and porsche in your content, cause it's part of the ContentDNA of this search term. The theory is quite larger of course, but I'm just summarizing.
I guess we go off-topic. The question is Will Google sustain the king of internet in future..? Let's continue discussion of this topic only.