The 'Market Watch'
is a section of MT4/MT5 which shows all BID/ASK prices and allows you to view instruments, place orders, open charts etc.
In order to see all instruments available for trading, please right click in the Market Watch window and select 'Show All'
To manually add the instruments you wish to see in the list, right click in the Market Watch window and select 'Symbols'
. You may also create custom sets.