Words like cedar/robin/linen come from either the physical or cultral environment that I (as a Chinese) wasn't exposed to when I was a child. Cedar and robin are all species native to Europe, and I guess they also appear in many Western fairy tales or historical stories.

Also, both because of the familiarity and how English form words, English assign very specific non-compound words to them (rather than "xxx tree/bird"), making it more difficult for people from a completely different language family to learn them.

But of course this is not only English. In Chinese a child is taught to act 孝 (filial piety, respect and obedience to parents) and know how your uncles 舅 (mother's brother) 伯 (father's elder brother) 叔 (father's younger brother) relate to your parents. I'm sure it's OK for a foreign learner not to master them.

Cedars, fwiw, are not found in most of Europe either. Small parts of the Mediterranean (also parts of the Himalayas, bizarrely; closer than you think!)

They likely show up in Western works a lot because they’re mentioned in the bible a good bit.