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