/(lib path)/dirAAA/ModuleA.pm
    /(lib path)/dirBBB/ModuleB.pm

##</code><code>##

    use lib ???;
    use ModuleB;

##</code><code>##

<code>
use lib '../dirAAA/'

##</code><code>##

use FindBin;
use lib "$FindBin::Bin/../dirAAA/"