"Tiom" (so many) is a little different than "multe" (many). Tiom implies a large given quantity (i.e. this many, without explicitly stating a number), whereas multe implies a large, but undefined amount. Vi povas havi tiom da sukero en la taso, aŭ vi povas havi multe sukero en via domo.
en:You can have so much sugar in the cup, or you can have a lot of sugar in your house. There is a fixed amount of sugar that will fit into the cup, but (practically speaking) unless you know the exact quantity there's just "a lot of sugar" in a space as large as a house.
Does that help?