Perhaps you should try some spelling variations:
"luan danh code snippets" » "luan thanh code snippets", "luan van code snippets", "luan nang code snippets", "luan danh co snippets", "luan danh code slippers"
"cong cau code snippets" » "cong cu code snippets", "cong chuc code snippets", "thong cau code snippets", "cong cau cong snippets", "cong cau de snippets", "cong cfd code snippets", "cong cau code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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 danh code snippets") or ("cong cau code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("luan danh code snippets") OR ("cong cau code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( luan danh code snippets ) or ( cong cau code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("luan danh code snippets") or ("cong cau code snippets"))) or ("locating bug code snippets"))*.