If you select some text and then press CTRL + F, the pod will open with that text entered as the Find string. It can then be used as described below.
The CTRL + Shift + F shortcut opens the pod with your previous search string. It can then be used as described below.
Use Basic Mode for simple searches. You can search the Current Project, the Current Window, Opened Topics or a selected folder. Current Window can be a topic or other pods
Changed in Adobe RoboHelp (2015 release) is that you can now limit your search to just the topic content as seen by the end-user. If you want to search in the code as well, tick Find in Source Code.
In Basic Mode you can use Regular Expressions.

In Advanced Mode you can set parameters rather than a specific search.
Regular Expressions are disabled in this mode as the parameters are using regular expressions so there would be a conflict.

The Replace Tab has the same options as the Find Tab plus an additional field where you can specify a Replace string.
Click Replace All to replace every instance without the option to leave or replace any specific instance. Do note the option to Backup Modified Files.
Click Find Next to find the each instance of the Find. For each instance either click Find Next to continue searching without replacing or click Replace to update the string and locate the next instance.
As in the Find Tab, you can use Regular Expressions for the Find but you cannot use them for the Replace.

