Perhaps you should try some spelling variations:
"duong duc dan snippets" » "luong duc dan snippets", "duong qua dan snippets", "dang duc dan snippets", "duong duoc dan snippets", "duong duc tan snippets", "duong duc dai snippets", "duong duc dan slippers"
"hang java java snippets" » "hang va java snippets", "hang java java slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("duong duc dan snippets") or ("hang java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duong duc dan snippets") OR ("hang java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duong duc dan snippets ) or ( hang java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duong duc dan snippets") or ("hang java java snippets"))) or ("locating bug code snippets"))*.