Using the above solution you can find the next occurence, vFind() takes the direction (1 for next, -1 for previous)
to get the page you can use: m_finder.find_get_page()..
You can alternatively use the following code to search yourself the entire pdf, and save the page number of the pages containing the search word:
int pagesCount = m_doc.GetPageCount();
for(int i = 0 ; i < pagesCount ; i++) {
    Page currentPage = m_doc.GetPage(i);
    currentPage.ObjsStart();
    Finder mFinder = currentPage.FindOpen(str, false, false);
    if( mFinder != null ) { 
    	int finds = mFinder.GetCount();
    	for(int j = 0 ; j < finds ; j++)  { 
		System.err.println("page " + (i+1));
		int foundIndex = mFinder.GetFirstChar(j);
		int phraseStartIndex = foundIndex - 50 < 0 ? 0 : foundIndex - 50;
		int phraseEndIndex = foundIndex + 50 < currentPage.ObjsGetCharCount() ? foundIndex + 50 : currentPage.ObjsGetCharCount() - 1;
		System.err.println("phrase " +  currentPage.ObjsGetString(phraseStartIndex, phraseEndIndex)); 
    	}
    	mFinder.Close();
     }    		
     currentPage.Close();
}