Perhaps you should try some spelling variations:
"luong cac den snippets" » "luong cuoc den snippets", "luong va den snippets", "luong tai den snippets", "luong cac dan snippets", "luong cac don snippets", "luong cac nen snippets"
"dung java java snippets" » "dung va java 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: (((("luong cac den snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luong cac den snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luong cac den snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luong cac den snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.