why search does work?

[leveryd]

[root@instance-fj5pftdp ~]# crash -v

crash 7.2.3-11.el7_9.1

crash> search -u AAAAAAAAABBB
crash> px 140691095166976
$12 = 0x7ff532c02000
crash> rd 0x7ff532c02000
    7ff532c02000:  4141414141414141                    AAAAAAAA
crash> search -u AAAAAAAA
crash>

i expect search -u AAAAAAAA can find out 7ff532c02000, but it does not.

[leveryd]

crash> search -u AB
7f08dff58ca8: ab
...
crash> rd 0x7f08dff58ca8
    7f08dff58ca8:  00000000000000ab                    ........
crash> x /10x 0x7f08dff58ca8
0x7f08dff58ca8: Cannot access memory at address 0x7f08dff58ca8

why x command can not access memory?