Auto complete for 2 tables

Hi all,
I’m using autocomplete in my application. I’m able to take values
from single table for auto complete. Now i need to take values from two
tables using many-to-many relationship.

Actually i have to tables items and orders table. Many-to-many
relationship between these two. I have another one table items_orders,
which have item_id and order_id in it. I need to show auto complete in
the following format

  "GH > Petrochemicals", where GH is in items table and

Petrochemicals is in orders table. Please give me some solution or
suggestion for this. It’ll be very helpful. Thanks to all in advance.