Wamor, you can try to change the option "Filter" when you search for your signals. Like for example to "Post-synthesis".
But maybe after synthesis some of the signals you have selected may get lost (signal name in RED), because they are not available. Usually it works, but not always.
The synthesis-tool is forced not to optimize special signals with KEEP.
--- Quote Start ---
constant debug : boolean := false; -- enable attribute for chipscope debug
attribute keep : boolean;
attribute keep of MasterTimeOutCounter : signal is debug;
--- Quote End ---