HoudahSpot gets you to your files quickly by helping you narrow down your search until only the relevant files are left over.
Find by Example lets you refine a search using a prototype file: a file that has something in common with the files you are looking for. Drag and drop a file from Finder or from the search results onto a search criterion. It will update to match that file. You just told HoudahSpot:
HoudahSpot 4.0 comes with a “droplet” that you can install in the Finder toolbar. This small application can be found from HoudahSpot > Preferences > Advanced. Follow the instructions found there to install Search.app as a Finder toolbar item.
When clicked, Search.app opens a new HoudahSpot window set to search the folder shown in the current Finder window. You can also drag and drop folders onto the toolbar item to open a new HoudahSpot window configured to search these folders.