Perhaps you should try some spelling variations:
"luan trinh o snippets" » "xuan trinh o snippets", "luan tinh o snippets", "luan tranh o snippets", "luan trinh do snippets", "luan trinh co snippets", "luan trinh mo snippets"
"python using java snippets" » "python using data 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: (((("luan trinh o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luan trinh o snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luan trinh o snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luan trinh o snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.