Perhaps you should try some spelling variations:
"dung chinh o snippets" » "dang chinh o snippets", "quang chinh o snippets", "tuong chinh o snippets", "dung chinh so snippets", "dung chinh do snippets", "dung chinh _ snippets"
"python using java snippets" » "python using data 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 chinh o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung chinh o snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung chinh o snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung chinh o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.