Perhaps you should try some spelling variations:
"dung ninh sio2 snippets" » "dung vinh sio2 snippets", "quang ninh sio2 snippets", "dung dich sio2 snippets", "dung ninh sio2 slippers"
"python using a snippets" » "python using a slippers"
"locating bug code snippets" » "locating bug code slippers", "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 ninh sio2 snippets") or ("python using a snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung ninh sio2 snippets") OR ("python using a snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung ninh sio2 snippets ) or ( python using a snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung ninh sio2 snippets") or ("python using a snippets"))) or ("locating bug code snippets"))*.