Abstract: This apparatus includes a keyboard for the search by user for successive regions of a microfiche bearing information which he needs, a microfiche reader itself having mechanically defined coordinates of the regions sought using the keyboard, and further having the capacity to project and present said regions and a control unit.It is characterized in that the control unit comprises a microprocessor (31) with which are associated a first memory (47) containing data relating to the operation of the different elements of the apparatus and a second plug-in memory (48) containing data associated with the information borne by the microfiche and defining a decision tree, the microprocessor transmitting instructions to the elements (35, 37, 39) of the apparatus to present complementary information, so that the user can continue his search within the decision tree.