Procedure for searching of data or a group of data in a database

The present invention deals with a method to search one item or a group of similar items within a number of items stored in a database, where each item is assigned with a representative graphical information, such as an image, sound, or text which identifies and characterizes the item itself. The method includes the following steps: a) organizing the database as a relational structure where all the representative information are grouped in a number of subsets according to a predetermined criterion of similarity, so that the information contained in each subset show differences in the informative content below a predetermined threshold value; b) associating to at least one of the subsets a probability value which depends on the subset content and/or from the results of previous search procedures and/or from the status of the ongoing search; c) randomly selecting one among the subsets according to the probability value assigned at the previous step, and simultaneously reproducing at least one part of the information contained in the same subset; d) if the searched item is not within the reproduced ones, repeating at least the previous step, until the user is able to find some interesting information.