Problems encountered in Linux learning-ask

Question 1:find Why can't I find the following *sample* file when I use "-a" command?

[[email protected] test]# Find/-name "USR"
/usr
/usr/share/doc/oddjob-0.30/sample/usr
/usr/share/gdb/auto-load/usr
[[email protected] test]# Find/-name "usr"-a-name "sample"
[[email protected] test]# Find/-name "usr"-a-name "*sample*"
[Email protected] test]#

Answer: This command is equivalent to finding a file which is called both USR and sample, contradiction! Question 2: Why can't I redirect the following command?

[Email protected] test]# ifconfig eth10
Eth10:error fetching interface Information:device not found
[Email protected] test]# ifconfig eth10 2>/dev/null
[Email protected] test]# ifconfig eth10 | grep ' interface ' 2>/dev/null
Eth10:error fetching interface Information:device not found
[Email protected] test]#

Problems encountered in Linux learning-ask