<li>{@code substring(string, start, [end])}: Returns a substring of the given string.</li>
            <li>{@code indexOf(string, substring)}: Returns the index of the first occurrence of substring in string, or -1 if not found.</li>
            <li>{@code contains(string, substring)}: Checks if the string contains the substring.</li>

    /** The key of the message: MS PowerPoint */
    public static final String LABELS_advance_search_filetype_powerpoint = "{labels.advance_search_filetype_powerpoint}";

    /** The key of the message: Occurence */
    public static final String LABELS_advance_search_occt = "{labels.advance_search_occt}";

    /** The key of the message: Anywhere in the page */