In English they can't either, it's a matter of spelling. They could write it as "fromhere", what it really is, just like the Russian отсюда could be safely written as от сюда, because it is etymologically a combination of от + сюда; the only difference is that Russian has the distinct static "here" (здесь) and dynamic "here" (сюда), and in our case we use the latter word because "from here" is dynamic.