This article shows how to search a string in a whole pdf file.

With this method you can use a Document instance to search a word in a whole pdf file and store/menage results.

public void customSearch(Document doc, String search){
    
    boolean caseSensitive = false;
    boolean wholeWord = false;
    
    for (int i = 0; i < doc.GetPageCount(); i++) {
        
        // get page
        Page page = doc.GetPage(i);
        page.ObjsStart();
        
        // find in page
        Page.Finder finder = page.FindOpen(search, caseSensitive, wholeWord);
                
        // manage each search term contained in this page
        for (int c = 0; c < finder.GetCount(); c++) {

            // start position
            int firstCharPos = finder.GetFirstChar(c);

            Log.w("---search---", "Page " + i);
            Log.w("---search---", "Pos : " + firstCharPos);

            // do custom actions

        }
        
        // close page
        page.Close();
    }

}