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