Hi -
It sounds like you want to create a segment that will pull back data for visitors who:
1) saw a specific page in one visit
then within 30 days
2) came back to your site in another visit
In order to create this segment, you need to use two visit containers in your segment and also use the "within" feature.
Here's how to do this:
1. Click on the gear on the right-hand side of the segment builder. Click on Add container (see orange box in the screen shot below).

2. In the newly added container, click on the icon to the left of the gear. Click on Visit (see pink box in the screen shot below)

3. Drag the "Page" Dimension into the container. Set it equal to the specific page name you want the visitor to see

4. Once again, click on the gear on the right-hand side of the segment builder. Click on Add container (see yellow box in the screen shot below).

5. In this newly added container, click on the icon to the left of the gear. Click on Visit (see green box in the screen shot below)

6. Drag the "Visit" metric into this newly added container. Select "exists" .

7. Click the clock icon beside the word "Then" Click on the word "Within" (see purple box in the screen shot below)

8. Click on the 1 and change it to 30 (see red circle in the screen shot below)

9. Click on the down arrow by "Week(s)" and change it to "Day(s)" (see screen shot below)

10. The final segment should look like this:

Thanks -
Sarah