Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van doan da snippets" » "van doanh da snippets", "van toan da snippets", "van hoan da snippets", "van doan dau snippets", "van doan va snippets", "van dan da 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 doan da 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 doan da snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van doan da snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van doan da snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.