Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"nam moi cong snippets" » "nam noi cong snippets", "nam voi cong snippets", "nam tai cong snippets", "nam moc cong snippets", "nam hoi cong snippets", "nam doi cong 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: (((("nam moi cong snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nam moi cong snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( nam moi cong snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("nam moi cong snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.