Based on what you've written, there may be some newer Splunk features that could help you.
First, if your lookup table originated as a database table, you could keep it in the database and use DBConnect to query the rows in the table appropriate to the search.
Two options:
https://splunkbase.splunk.com/app/958/
https://splunkbase.splunk.com/app/2686/
Another option is to use Splunk's new features: KV Store. You can think of it as sort of Splunk's take on an internal database. It has several advantages over lookup tables including being able to handle more data and more quickly.
http://dev.splunk.com/view/webframework-features/SP-CAAAEZK
In both cases (and, in truth, in the case of just plain lookup tables), you can solve your problem by some combination of the following approaches:
Bring in the lookup table and then filter for rows with the "Match" value that you need in that particular search. (So,
Create two lookup tables, one with "Match" for Products, the other with "Match" for Description.
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