Current search engines do not process queries semantics. However, most of the times contexts of use embed ontologies that do provide meanings. The paper suggests that the capability to satisfy users? queries is at variance with the level of ontology complexity. When extracting information from simple ontologies, the search engines are able to satisfy easily queries because the ambiguity of interpretation of terms and relations is very little or non-existent. The paper identifies and describes four different categories of information search (so-called "ideal types of information search"), that show a growing level of complexity. At the highest level of complexity they present an higher level of ambiguity. This means that meanings might be embedded in more ontologies and/or use contexts. Finally, the paper suggests that scenario analysis can enable to characterize the ontologies of use contexts by means of Web services and Personalization tools.