Hi @JohnR,
Sorry for such long delays you are facing in searching items. Is the delay of 4 second is there on Windows 10 Phone or Desktop? For desktops running UWP App, it shouldn't be so much.
By default, Enpass performs deep search i.e. in all fields of a item, so it takes time to decrypt and search in each field of each item and the Microsoft UWP App takes long time in performing cryptography operations compared to any other platform. More items means more search time. Mobile phones have less processing power than desktops, so UWP App on Windows Phone tends to be more impacted.
I should clarify here that Enpass searches very smoothly on all other platforms without any noticeable delay. Its our bad here in UWP App, that we don't show progress wheel while searching, but a fix to that is underway.
The solution for faster search is to search in title of item only. You can turn on this option in "Settings->Customize->Search in->Title only".