I had this problem too, I'll share my workaround, maybe you'll find it intuitive as I do.
- In DOpus, go to Preferences, File Displays, FAYT and Filter Bar Keys.
- Change Default mode (no activation key required) to Filter
- In Listary Settings, General, change Prefix to disable find.... to ` (tilde key). I find this useful as I don't have to press shift+8 fifty times per day.
Now in Dopus, just press ` to disable Listary, then type to use the filter bar. This is second nature to me now.
There are many ways to achieve this; the critical step is using the disable key in Listary