Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"phap hoc den snippets" » "phap hoan den snippets", "phap mo den snippets", "phap han den snippets", "phap hoc dan snippets", "phap hoc de snippets", "phap hoc hien 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: (((("phap hoc den snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("phap hoc den snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( phap hoc den snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("phap hoc den snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.