Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van cong he snippets" » "van dong he snippets", "van phong he snippets", "phan cong he snippets", "van cong che snippets", "van cong ha snippets", "van cong de 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: (((("van cong he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("van cong he snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van cong he snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van cong he snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.