Can Farm who or what? I feel like you should have a goal if you are "Farming". You can go to Grizzleheim if you have talked to Bauldur and reached level 20. (He's in Olde Town)
There is always something to farm, I myself have farmed Savarstaad Pass for couch potatoes, If you want a particular item, you should search it, then see what mobs or bosses drop it. As a level 21, there won't be much to farm so I would recommend wait till later in the game. Good Hunting.
Most of the mobs drop couch potatoes which are very useful for gardening and pet training. Plant enough and at your harvest you'll be rich with mega pet snacks. The troubled warriors are one of many that drops this item.