Those are three separate medication names, not one with backslashes in it. So you would search for them individually or in combinations with logical operators.
The two NDCs you mentioned are indeed not in the database. openFDA generates its NDC dataset from the downloadable files available at the FDA, and we have verified the two NDCs are not present in those files, which is why they are also missing from openFDA.
FDA National Drug Code Directory search does bring results for those two NDCs; however, they are ...
You could query the Device Recall Enforcement endpoint in openFDA with the information you have available. For example, if you have a device model name, you could query against the product_description field, which often contains model name, number or other relevant information: