I run into this problem from time to time, and I can't remember whether it's been reported on this particular board or not. Namely, occasionally a wildcard search that appears to comply with all the wildcard rules nevertheless gives me the dread "Too many matches with the wildcard search" error.
On this occasion, I was searching for Charles Lucia who died in 1968. If you search for "charles lucia" who died in 1968, the search works perfectly. But I seldom search for "charles" because of the prevalance of "chas", "charley", "charlie", etc. I usually just search for "cha*". So in this case, I searched for "cha* lucia" who died in 1968, and got the error. I switched to searching for "charles lucia" as described above, and all was well. But I was wondering why this wildcard search didn't work.
As always, my search was exact.