So in English when we say, "It's just a drop in the bucket." we're talking about only having
a small amount of something when we need a whole lot more of something.
So a good way to look at this would be let's say you're planning on going on a trip and
the trip costs $3000 and so far you have saved up $10.
That would be a really good time to say that $10 it's a drop in the bucket.
So imagine that you have a bucket or a pail and you're trying to fill it up with water
and you're only putting one drop of water in at a time.
That's where this saying comes from.
So you need $3000 and you only $10.
You could easily say, "It's just a drop in the bucket."