Lets put it in another way that Robert Schmidt might say (He's the translator of Greek and high ranking scholar I worked with as a programmer)... It's hard to get a 100% semantic field match between words. Many languages have words that just don't translate into English, while some words might have some of the meaning and would be synonyms. While their semantic fields will overlap, they are not a perfect match because their auxiliary meanings don't match. This is what I'm trying to get across.