The search engine on the GTN is very unforgiving. You must spell the name of the item exactly correctly and make sure none of the options are checked which would eliminate a hit. This could be part of your problem.
Most especially, you have to NOT choose anything in the "Usable By" droplist. Any choice on that will get you no results.
Which GTN terminal you use makes no difference. Unlike at launch, it's a single system shared by both factions.