Perhaps you should try some spelling variations:
"dung cong lan slippers" » "dung trong lan slippers", "dung cong luan slippers", "dung cong lang slippers", "dung cong san slippers", "dung cong lan slippery", "dung cong lan grippers"
"dung java java snippets" » "dung va java snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("dung cong lan slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung cong lan slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung cong lan slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung cong lan slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.