Means you are simply connected to an ultrapeer. The ultrapeer helps filter out unnecessary messages. Leafs connect to ultrapeers in order to connect to the network.

Not all ultrapeers are good. There are some spam ultrapeers out there. Also, some people using earlier versions of LW would 'force' themselves to become ultrapeers when their LW didn't really behave well in that mode, thus affecting other's searches & connections. LW tried to stop people doing that in later versions of LW. There are also 'dud' ultrapeers, deliberately set up to affect the network. Those ones will block search messages.

So sometimes if searches are bad (continual zero search results), it can be worth removing the ultrapeer you have been connected to the longest. However, depending on person it may take from a few seconds to a few minutes to get a stable replacement ultrapeer & good connection back.