Problem with sniffing with wireshark even using hub

[kiarad]

I am using wireshark to sniff packet from my neighbor computers which all connected to the same hub as mines. but I just could see the packets of my own laptop and no record from the neighbor laptops.
we all are connected to a D-Link DE-805TP hub which according to wireshark manual is areal hub not switch. this hub from other side is connected to switch which is connected to rotour.
My laptop ethernet card is :
"Broadcom NetXtreme Gigabit Ethernet"
and I am trying to capture under promiscuous mode. I ma using a portable version of wireshrk.
So I wonder where is my mistake and how I can resolve it. personally I think sniffing is ok becuse I can see the packets in TCP or UDP or POP protocols from my own IP but no trace of other IP's activity. also other IP's "who is" broadcasting are come to capture window but as I told there is no packet.

let me to clarify again the network map for details.

4 computer with local IP are connected to "D-Link DE-805TP" hub this hub (because has not uplink port) is connected using a crossover cable to "centreCOM MR820TLX) hub/switch and this switch is connected to roto
r.

Please let me to know what is the problem.