Instead of having four extremely similar functions there should be only one Find/Replace.
Often when searching for something you realize that you want to replace it. Equally often you want to change the scope 
of the search(&replace). Every once in a while you even want to switch from "search in file" directly to "replace in 
project" or similar. It's very convenient if all of it is controlled from one place.
E.g., jEdit uses a single find/replace window and ever since I tried it other editors' separate find and replace 
windows have felt needlessly and annoyingly cumbersome.