String titles = post.getString(KEY_TITLE);
titles = Html.fromHtml(titles).toString();
String author = post.getString(KEY_AUTHOR);
author = Html.fromHtml(titles).toString();
String thumbnail = post.getString(KEY_THUMBNAIL);
thumbnail = Html.fromHtml(titles).toString();
must change to
String titles = post.getString(KEY_TITLE);
titles = Html.fromHtml(titles).toString();
String author = post.getString(KEY_AUTHOR);
author = Html.fromHtml(author ).toString();
String thumbnail = post.getString(KEY_THUMBNAIL);
thumbnail = Html.fromHtml(thumbnail ).toString();