Intelligence of humankind mostly includes five parts: the observing ability, the memory ability, the practice ability, the thought ability, the imagining ability, etc.. In this paper, an intelligent behaviour, which people search the book in library, is discussed. By contrasting in references of book and linkage of Web pages, we proposed that the process of searching information on Internet is similar as book search. And so, we proposed that Search Engines take on the five intelligence behaviours corresponding five parts intelligence of humankind: the apperceiving behaviour, the memory behaviour, the learning behaviour, the thought behaviour, the comprehension behaviour. We divided the process of information searching of search engine into four stages: classifying Web page, confirming a scope of information searching, crawling Web pages in internet, and filtrating the result Web pages. Finally, we proposed an intelligent model (Outer net internet inner net, Three Net Model) of impleme...