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