Why pip search can't find certain packages (for example, html5lib) while they can be installed via pip install anyway?
E:\software\Python276\Scripts>pip search html5lib
html5lib-truncation - Truncating HTML with html5lib filter
HTML-Sanitizer-With-IFrame - Extends Python html5lib's sanitizer.HTMLSanitizer
to allow iframe elements.
microdata - html5lib extension for parsing microdata
html5tidy - Simple wrapper around html5lib & lxml.etree to
"tidy" html in the wild to well-formed xml/html
E:\software\Python276\Scripts>pip install html5lib
Downloading/unpacking html5lib
Running setup.py (path:c:\users\user\appdata\local\temp\pip_build_user\html5lib\setup.py) egg_info for package html5lib
Requirement already satisfied (use --upgrade to upgrade): six in e:\software\python276\lib\site-packages (from html5lib)
Installing collected packages: html5lib
Running setup.py install for html5lib
Successfully installed html5lib
Cleaning up...