What you see depends on what relays you're connected to as well. Some of the default relays in Iris have a tendency to disconnect and reconnect and that causes notes to appear and disappear in your feed. Look at the relay list and delete any that show white dots periodically. Then go to nostr.watch and add a few new ones. Add 3-4 that are geographically close to you. And then add 3-4 that are located in other countries that speak your native language, like UK and Australia.