To improve the search feature, try using tags on your content to allow for more searchable keywords.

You can do this in Admin Portal > Publish > Find the desired file (This can be done during or after upload) > right-click the file > select File Properties > scroll down to Tags > Edit Tags > Enter Tags and Save (you can have multiple tags per file to make it easier to search).

You can also create Tags to make Courses more searchable. This can be done when creating the Course in the Course Settings Tab. You can also add to an existing Course by locating the Course in the Courses Tab and selecting Menu > Course Settings > Tags field.