I have changed my OS X Yosemite shell to Zsh and configured with oh my zsh  plugins, recently i installed proxychains-ng to proxy command line tools, but i found zsh completion does not work on the command after proxychains4, likeproxychains4 wget [hit tab], will not come up with wget's optionsproxychains4 gi[tab], will not come up with gitAnd zsh does not work on command after alias either,alias proxy=http_proxy=http://127.0.0.1:12345proxy brew[hit tab], will not come up with brew's subcommandsthere will be no completions for command and it's option. Any idea? thank you. 
Zsh completion on the second command or after an alias?
zsh;autocomplete