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