Transact SQL :: XML Not Using Proper Index?

I have two xml queries that take long: the 1st query takes about 5 minutes (returns 700 rows) and the 2nd query takes about 10 minutes (returns 4 rows). The total rows in the table is about 2 million. There are three secondary indexes: Property, Value and Path in addition to the clustered index on CardID and Primary XML index. Here is the table definition: 

CREATE TABLE [dbo].[Cards]
(
[CardId] [int] NOT NULL,
[Card] [xml] NOT NULL,
CONSTRAINT [PK_dbo_Cards_CardId] PRIMARY KEY CLUSTERED
([CardId] ASC)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]

[code]...

Looking at the execution plan, the query uses the Primary XML Index even if I add any of the secondary xml indexes. My question is why does not the optimizer use the Property 2ndary index instead of the Primary XML Index? Microsoft recommends that creating a Property index for Value() method of the xml datatype would work to provide a performance benefit. What would be another alternative to make the query run faster?