One language is certainly not sufficient to convey entire detailed feelings, nuances, attitudes, and phenomena that consist of the human experience. The existence of several untranslatable words in other languages would definitely attest to that. A few would even go so far as to say that language itself cannot completely handle this task.
Then again, they perhaps never heard the word schnapsidee (a German word used for ideas and plans so farcical that only a drunk individual could have concocted them), or meriggiare (an Italian word for the quite specific act of resting in the shade during noon).
We have methods of describing these words in English — it is simply that other languages could sometimes do the same thing in a manner more efficient than one word.
Here are some untranslatable words you certainly require to add to your everyday vocabulary.
Lampadato (Italian)
The beautiful orange glow that comes through being addicted to tanning salons.
Schnapsidee (German)
Ideas and perceptions are so farcical that they should have been conceived while drunk.
Gula (Spanish)
Gluttony, indulgence, greed eating merely for the taste (i.e., not because of hunger).
Schadenfreude (German)
The feeling of joy and pleasure when one gets to see another one fail or suffer misfortune.
Gattara (Italian)
A woman who dedicates herself to stray cats.
Seigneur-terraces (French)
Coffee shop occupants sit at tables for a long time but spend quite a small amount.
L’esprit de l’escalier (French)
To be exact, stairwell wit—an extremely late retort considered of merely after departure.