I may have missed this in the documentation, but:
(1) What characters are indexed and can be the target of a search? For example, I’ve found that I can search for a “$” but not a “/”.
(2) What characters constitute a word boundary? For example, in TextEdit “860.555.1212” is one word, whereas “(860)555-1212” is three words.
Also, a couple suggestions:
(a) Consider adding the ability to search only in the record document and not in any of the associated metadata.
(b) Consider providing the ability to refer to a parent tag rather that each individual sibling tag. For example, if I had a “Status” tag with 10 children, I’d like to be able to create a Smart folder for items that had no Status assigned, without explicitly listing the 10 child tags.