Laptop will not find Google sites when wireless

Hi, We just got our wireless home network set up & the only problem is
that although the laptop will find the network and connects to most
pages well, if we try to find anything with "google" in the URL it will
not connect to any link at all.

If connected by wire to the network, it all works fine (& so do the 2
PCs) - its just the wireless access that has a hole in it somewhere.

Any suggestions please for what might be wrong or needs resetting?
Anyone else had this problem? Its really awful as we use Google for
everything - its like having your arm cut off!
Many thanks,
Gill