+++ This bug was initially created as a clone of Bug #44954 +++ It would be nice if the "Find Record" dialog had an option to search through all forms of the current document instead of only through the current form. This would require some more intelligence (going through the implicit joins that underly the relationship between the forms, and all that), but doable. It is probably best to implement this along with - or maybe after - bug 44954.
Confirmed this one and left as medium priority. Great idea, we'll see if we can get someone working on it.
Adding self to CC if not already on