Can we have two irule for the same virtual server, But running only one based on url ?

Do you need them to executed based on two different HTTP HOST names or two different URIs?

when HTTP_REQUEST {
    if {[HTTP::host] starts_with "something.com" } {
        Execute something.com iRule
    }
    elseif {[HTTP::host] starts_with "somethingElse.com" } {
        Execute somethingElse.com iRule
    }
    else {
        return
    }
}

or

when HTTP_REQUEST {
    if {[HTTP::uri] starts_with "/something" } {
        Execute something iRule
    }
    elseif {[HTTP::uri] starts_with "/somethingElse" } {
        Execute somethingElse iRule
    }
    else {
        return
    }
}