DSXchange

what I should change after I received the error msg "TOSH 000205 " Path search failure :"in Parallel datastage ?

You should change the setting on your individual typing style from TERSE to VERBOSE.
Additionally, as a guess I'll venture the opinion that the path to whatever is being searched for on the server is in some way unavailable.

Path search failure suggests that one of the search list environment variables (PATH, LD_LIBRARY_PATH, CLASSPATH, etc.) needs extra information (extra directory pathnames).