I you want to hunt one at a time:
Dry piece of wood - kill Bane bringer underground of Green Claw Swamp
Goblin Ear - kill Goblins on west of Edron
Lump of Dirt - kill Rotworms in Vandura caves
Spider Fangs - kill spider and tarantulas in spider caves near Port Hope
Bat Wing - kill Bat or Mutated Bat in Yalahar or Vengoth
Centipede Leg - kill centipedes on Tiquanda or Trapwood Dworcs Lair
Marsh Stalker Beak - kill Marsh Stalker in Dryad gardens in cormaya
Scorpion Tail - kill scorpions in Darashia montains (if you are low level) or Plains of Havoc
Lancet - kill blood priest and blood hand in Drefia
Minotaur Horn - kill all types of Minotaurs in Minotaur Pyramid in darashia or Mintwallin under Thais
Small Flask of Eyedrops - kill Bonelords, Elder Bonelords or Gazer in Bonelords' Cave in Fenrock or Vandura
Sulphurous Stone - kill Stone Golen in Stone Golem Cave on Formorgar Glacier or Hrodmir
Tarantula Egg - kill Tarantulas in spider caves near Port Hope
if you want to farm several items together:
In marshland next to Venore you can find Marsh Stalker, Scorpion, Rotworms, Bat
In Plains of Havoc and Dark Cathedral you can find Minotaurs, Bat, Centipede, Scorpion, Bonelord, Stone Golen, Tarantulas, Spiders, Rotworms
Sources: tibiawiki.com.br and tibia.fandom.com