In Redwood Purchasing/Process Requisitions, how do exclude or do a does not contain? and sorting Q

Summary:

In the search, in order to assign requisitions out effectively, we do a search excluding a supplier, how is this possible in Redwood without selecting every other supplier in the system?

Also how does the sorting work, when clicking sort on subsequent columns, we would like to do sort descending requisition order and then descending date approval order, which was done in classic with the advanced search tool, in this scenario, we can't tell when sorting one column after the other if it takes the previous sort into consideration and if so what order we should do this?

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