Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"duc so toan snippets" » "duc so tan snippets", "duc so than snippets", "duc bao toan snippets", "duc mo toan snippets", "duc sy 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: (((("duc so 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: (((("duc so toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duc so toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duc so toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.