1 Discover 'john' in cat.contact:

     2     DOC (3): John London

     3     DOC (1): John Smith

     4 

     5 Discover 'jane' in cat.contact:

     6     DOC (2): Jane Smith

     7 

     8 Discover 'smith' in cat.contact:

     9     DOC (4):  Smith

    10     DOC (2): Jane Smith

    11     DOC (1): John Smith

    12 

    13 Discover 'j' in cat.contact:

    14     DOC (3): John London

    15     DOC (2): Jane Smith

    16     DOC (1): John Smith

    17