Xah Lee has a couple of useful tutorials on the finer points of ibuffer and the isearch family. Every Emacs user is familiar with forward and backward incremental search, 【Ctrl+s】and 【Ctrl+r】, but there are some more specialized commands as well. For example, there are isearch-forward-word (【Meta+s w】) and isearch-forward-symbol (【Meta+s _】). These differ subtly from the usual isearch-forward; see Xah’s Search & Highlight Words for the details and for other useful commands.
Most people don’t use these commands very often so they’re hard to remember. I have guide-key set to pop up the bindings when I type 【Meta+s】 so I don’t have to remember worrying about remembering them. Another good solution would be to make them into a hydra.
The default buffer listing function is list-buffers but you should replace that with ibuffer. It turns out the ibuffer has many ways of marking and operating on buffers. Most folks know how to mark and delete buffers but you can also perform save, search, revert, rename and several other useful functions. Again, you should check out Xah’s tutorial on the subject for the details.
These are useful tutorials and you may want to bookmark them but you should at least give them a look.
UPDATE: regex → incremental