These items are not too difficult to find globally, but if you follow the guidelines below, you should see more than what you would need.
Crystal Chunks
South of the Dunyu Ruins, right before you reach Lingju Pass, there’s a teleportation point where you can go to.
A little bit west to northwest of this spot, you should find a location where you’ll be able to farm crystal chunks. Another area you can teleport to is at Lisha, just west of the waypoint.
There should be an area where you’ll find lots of nodes for crystal chunks. Lastly, you should see some nodes as well near Jueyun Karst.
Philanemo Mushrooms
These mushrooms are not that hard to find. They’re pretty standard in the city of Mondstadt. You need to look around the houses.
You can usually find them near the rooftops or just around the walls. It’s straightforward to get around 13 to 14 per go about, so you’ll be able to get a lot.