Android – firebase searches by character

I use firebaserecycleradapter in my firebase application. Until now, I don't know how to search firebase by character. I have used query, but I get a good result, but it is not available. Here is the database search I want:

This is my method. I use it, but if I only enter the full name, it gets "user name", so if I write "m", it does not display:

mMainSearcher.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {

            Query Q = mDatabase.child("Users").orderByChild("Username").equalTo(newText);

            FirebaseRecyclerAdapter<Getting_Friends, Search.SearchViewHolder> firebaseRecyclerAdapter22 = new FirebaseRecyclerAdapter<Getting_Friends, Search.SearchViewHolder>(
                    Getting_Friends.class, R.layout.my_friends_card, Search.SearchViewHolder.class, Q) {
                @Override
                protected void populateViewHolder(final Search.SearchViewHolder viewHolder, final Getting_Friends model, int position) {

                    viewHolder.setUsername(model.getUsername());
                    viewHolder.setProfile(getApplicationContext(), model.getProfile());

                }
            };
            mFriendsRecyclerView.setAdapter(firebaseRecyclerAdapter22);
        return false;
        }
    });

This is what I get when I enter my full name:

This is the result when I write "m" or "m":

So I just need > > when I write "m" automatically, all user names starting with "m" must be displayed as Mike

resolvent:

Try this

Query Q = mDatabase.child("Users").orderByChild("Username").startAt(newText).endAt("~");