Chess.com-Book opening

Is your 'book opening' up to date ? Well why is that I am not seeing anything on ECO E58 here ?

got this from wikibooks.org

E58 Nimzo-Indian, 4.e3, Main line with 8...Bxc3: 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5 6. Bd3 c5 7. O-O Nc6 8. a3 Bxc3 9. bxc3

That's a very popular and main line. Haven't seen how the 'opening book' works but can it be reached by one of the other move orders?

I think is under ECO E57 here

This might prove useful (if dated):

http://www.exeterchessclub.org.uk/ecocodes.html

It appears as if the difference between E57 and E58 doesn't occur until Black's eighth move.

E58     1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5 6. Bd3 c5 7. O-O Nc6 8. a3 Bc3 9. bc3

I got this from here