Hi Mike, great code!
It works fine for me in general but I´m having problems when a word begins with "and" or with "or" like "orthopedics".
I´ve change, in SearchGrammar.cs OrOperator.Rule = Symbol("or") for OrOperator.Rule = Symbol("or ") (note the blank space after the "or") and it works, but I´m not sure its a good solution.
I´m also having problems is with one letter words, if you search "when I grow up" doesn´t return any result, but if you search "when grow up" it returns matching records including the one who has "when I grow up". FORMSOF (INFLECTIONAL, I) returns nothing.