TextWatcher doesn't clear ListView after deleting EditText

I have a EditText which works with a TextWatcher. It is for searching in a database. When the user types more than one charackter into the EditText, the db query searchs for results and puts the results into a ListView. But if the user types something in and then delete all charackters, the ListView shows nearly all results of the db... thats my problem. I want, that then nothing is shown anymore.

TextWatcher:

@Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            if (count <= before) {
                searchGrammar.clear();
            } else if (count >= before) {
                searchGrammar.clear();
            }
        }

        @Override
        public void afterTextChanged(Editable s) {
            if (s == null) {
                searchGrammar.clear();
            } else {
                sText = etSearch.getText().toString();
            }
            populateSearchList(db.getSearchData(sText));
            populateListView();
            registerClickCallback();
        }

Methods:

private void populateSearchList(Cursor result) {
    while (result.moveToNext()) {
        searchGrammar.add(new SearchList((result.getString(1)), (result.getString(2))));
    }
}

private void populateListView() {
    ArrayAdapter<SearchList> sAdapter = new SearchListAdapter();
    ListView sList = (ListView) findViewById(R.id.main_lV);
    sList.setAdapter(sAdapter);
}

private class SearchListAdapter extends ArrayAdapter<SearchList> {
    public SearchListAdapter() {
        super(MainActivity.this, R.layout.content_grammar_search, searchGrammar);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View itemView = convertView;
        if (itemView == null) {
            itemView = getLayoutInflater().inflate(R.layout.content_grammar_search, parent, false);
        }

        SearchList currentGrammar = searchGrammar.get(position);

        TextView headT = (TextView) itemView.findViewById(R.id.cgs_tVHead);
        headT.setText(Html.fromHtml(currentGrammar.getContent()));

        TextView examplT = (TextView) itemView.findViewById(R.id.cgs_tVExpl);
        examplT.setText(Html.fromHtml(currentGrammar.getExample()));

        return itemView;
    }
}

SQLite query:

public Cursor getSearchData(String content) {
    SQLiteDatabase db = this.getWritableDatabase();
    Cursor result = db.rawQuery("SELECT * FROM " + TABLE_NAME + " WHERE " + COL_2 + " LIKE '" + content + "%' LIMIT 5", null);
    return result;
}

I noticed, that the ListView is showing then (after input and deleting) all the time the same results, not even new ones.

Thank you very much in advance