Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"hieu van doc snippets" » "hieu va doc snippets", "thien van doc snippets", "lieu va doc snippets", "hieu van duoc snippets", "hieu van hoc snippets", "hieu van loc 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: (((("hieu van doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hieu van doc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hieu van doc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hieu van doc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.