Let me first explain what happens when you perform searching by type - JustDecompile will traverse through all of the types in the currently presented assemblies in the treeview. In those cases you should specified a single word that will be used for the search criteria. For example if you type "string", JustDecompile will check all of the types name that contains or are equals to the given word token. You can also specify a full search name - the name of the type and its namespace declaration separated by a comma character - "system.string". Searching by symbol has some differences. It accepts only a single search word. JustDecompile will check all of the Type's member names(field, property, method or event) for any coincidences. In your case you should type only "IsPostBack", when searching by symbol. I hope this clarifies your question. Let us know if you need any further explanations.