If I look at this page, the query you're looking for would look like this in JSON notation for example 'x>10':

{x:{$gt:10}}

in Delphi notation this could be written as:

BSON(['x',BSON(['$gt',10])])

or in the condensed form (where one BSON call does the embedded levels):

BSON([x,'[','$gt',10,']'])

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