Welcome to LQ.
The most yum commands has to done with : 1) su <enter password>
2) yum <option> <option>
The most used yum commands :
Find a package name : yum search <name> ( or part of name ).
The same, searching for several packages :
yum search <name> <name> <name> <name> <name>
Installing one or more packages : yum install <package>
yum install <package> <package> <package> <package> <package>
Finding which package to install, to get a certain file :
yum provides */<file name>
The yum manual : Just type 'man yum'.
Or read on-line
http://linux.die.net/man/8/yum
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