Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van tuan dot snippets" » "van quan dot snippets", "van ban dot snippets", "anh tuan dot snippets", "van tuan do snippets", "van truan doi snippets", "van quan doi 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: (((("van tuan dot snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("van tuan dot snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van tuan dot snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van tuan dot snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.