search interface clarity

[annamorphism]

I happened across this now two-year-old class discussion of CU today: https://liturgicalmanuscriptsdh.pubpub.org/pub/oj8hs3o9/release/3

Some critiques in their mostly positive experiences:

1. "[the terms it uses] are not intuitive! Is there an expectation that Cantus Ultimus Users be familiar with CANTUS Database?"
2. "I found Cantus Ultimus’s search function confusing to use, especially compared to Cantus Database’s. The latter provides much more instructions for searching and a clearer sense of acceptable entries for each field."
   2b) (same comment re-written)[CantusDB] gives clear examples of the types of terms that are acceptable in each search feature, and allows for searches restricted by multiple fields. Cantus Ultimus is much less clear about what kind of searches can be performed, and about what different fields mean."

The dropdown of restricted vocabulary (which I don't think they had at the time) solves some of their issues, but we could probably do a better job of referring to CantusDB's documentation about the various fields and how to search them.
Searches restricted by multiple fields also seems like a valuable thing to have.