Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van luc chen snippets" » "van duc chien snippets", "van luc thien snippets", "van luc nhan snippets", "van loc chen snippets", "van duc chen snippets", "van lu chen 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 luc chen 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 luc chen snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van luc chen snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van luc chen snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.