NetSuite imposes a few limitations on saved searches. Calcualted columns (formulas) cannot be retrieved via the NetSuite API. Only columns directly from the table may be retrieved. If you have a calculation in your saved search, you would need to return each individual column used in the calculation and perform the calculation client side. Ie:

Saved searches that return an aggregation or summary (Group / Count / Sum / Minimum / Maximum / Average) cannot be returned at all. The NetSuite API will throw an exception upon attempting to retrieve these saved searches. Due to this limitation, these saved searches are unavailable for our and any other third party tool.