Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"vat dan toan snippets" » "vat van toan snippets", "vat dan than snippets", "vat manh toan snippets", "va dan toan snippets", "van dan toan snippets", "vat ran 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: (((("vat dan 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: (((("vat dan toan snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( vat dan toan snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("vat dan toan snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.