adding description or synonyms when the autocomplete

form textfield is used.how do i make something like this ?
i believe that this is not so hard to do but i am totally new to drupal and i find it kind of difficult.
So if for example i have entered under the terms of a vocab. USA United States of America or U.S.A how do i make them
appear side by side when i start typing at the form fied with tags option enabled ( at the autocomplete form textfield).
Basically an sql query will select all the synonyms of the the term i'm typing and will show them as synonyms.
another example could be for product codes and description .
e.g
123->apples
124->bananas
125->oranges
126->lemons
etc etc.