When probing for record syntaxes, try an all-records search.
This gives us a chance of finding something in Russian-language targets such as
http://irspy.indexdata.com/full.html?id=Z39.50%3Ans1.gbs.spb.ru%3A212%2Fnmagpl
in which we can't find any records using the standard English-language searches.
"\@attr 1=4 computer",
"\@attr 1=44 mineral", # Smithsonian doesn't support AP 4!
"\@attr 1=1016 water", # Connector Framework only does 1016
+ "\@attr 1=1016 \@attr 2=103 x", # Find all records
### We can add more queries here
);