Perhaps you should try some spelling variations:
"trang trinh do snippets" » "tra trinh do snippets", "trang tri do snippets", "thanh trinh do snippets", "trang trinh ky snippets"
"luong java java snippets" » "luong 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 java java snippets") or ("trang trinh do snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luong java java snippets") OR ("trang trinh do snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luong java java snippets ) or ( trang trinh do snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luong java java snippets") or ("trang trinh do snippets"))) or ("locating bug code snippets"))*.