Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"doan vi toan snippets" » "doan va toan snippets", "don vi toan snippets", "doan thi toan snippets", "doan vi than snippets", "doan bai toan 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: (((("doan vi toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("doan vi toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( doan vi toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doan vi toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.