Wifi not appearing on my list

Wifi not appearing on my list

So here's my problem: I have an ASUS RT-G32 Wifi Router that I am using
for my connection and when I'm at home I can connect from Ubuntu,Windows 8
& My CyanogenMod 10.1.3 Galaxy S4....when I'm at college(I am on the same
provider,made contract with them,I live on a rent) My windows 8 sees the
WiFi and connects to it,My android sees the connection but doesn't connect
to it and Ubuntu doesn't even see it.A week ago i tested this with another
router Asus RT-N10E and the problem was the same(then i thought it was
from the router) but now I'm running out of ideeas.
Help Please???