Perhaps you should try some spelling variations:
"dong dot trong slippers" » "dong ro trong slippers", "dong dat trong slippers", "dong do trong slippers", "cong dot trong slippers", "dong dot trong slippery", "dong dot trong 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: (((("dong dot trong slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dong dot trong slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong dot trong slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong dot trong slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.