Category pattern matching on transactions?

When I import OFX files there are multiple entries from the same expense, such as the local supermarket where I buy all my food. However moneeydance doesn't seem to 'remember' which category they go into and I find myself repeatedly adding it to "Personal: Groceries" every time it pops up, this is just one example of many.

Am I missing some way to basically tell it that any transaction starting with "Somerfields" will default to the correct category before I record it. It certainly would be helpful.

I have looked through the User Guide but unable to see a solution, somewhere to add "Somerfields *" (note the asterix on the end) would be great

edit: I should have said that the 'normal' transaction matching isn't working due to a number of my transactions showing up with ever changing Ref numbers on the transaction, such as:
SOMERFIELD 5433 REF 870 0645928