OrderSearchCustomType:
    | "BooleanType"
    | "DateTimeType"
    | "DateType"
    | "EnumType"
    | "LocalizedEnumType"
    | "LocalizedStringType"
    | "NumberType"
    | "SetType.DateTimeType"
    | "SetType.DateType"
    | "SetType.EnumType"
    | "SetType.LocalizedEnumType"
    | "SetType.LocalizedStringType"
    | "SetType.NumberType"
    | "SetType.StringType"
    | "SetType.TimeType"
    | "StringType"
    | "TimeType"
    | string

Possible values for the customType property on query expressions indicating the data type of the field.