I was able to solve this problem!
Thank you, valuable advice!
I had overlooked the important part of the setting.

The thing what I want to do is what displaying a number as follows.
—–
1.1
1.2
1.3
1.4
2.1
2.2
2.3
2.4
3.1
3.2
3.3
3.4
4.1
…
—–
In order to implement above list,
I made four styles of bullets or numbering based on given advice.

After that, I inputted number as follows in “Numbering style”.

1.^#.^t <- 1.1, 1.2, 1.3, 1.4
2.^#.^t <- 2.1, 2.2, 2.3, 2.4
3.^#.^t <- 3.1, 3.2, 3.3, 3.4
4.^#.^t <- 4.1, 4.2, 4.3, 4.4

(I made pdf that visualized above method. Please see the following link)

https://drive.google.com/file/d/0B1krZZFZLPH6SDRPTUM5MTNFS2s/view?usp=sharing

I couldn’t notice method that removes “^” before each number(1,2,3,4…) until it.
By this method, if I want to start from 1.1, I choose Paragraph style which inputted 1.^#.^t ,
In case of starting from 2.1, I can use Paragraph style which inputted 2.^#.^t ,

It was easy. I’m sorry.
This solution may be little tricky.
However, I cannot find other solution.
Thank you indeed for your advice!