Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets"
"van cong duc snippets" » "van dong duc snippets", "van phong duc snippets", "phan cong duc snippets", "van cong suc snippets", "van hong duc snippets", "van cong dac snippets"
"locating bug core snippets" » "locating bug code snippets"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("using java code snippets") or ("van cong duc snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("van cong duc snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( van cong duc snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("van cong duc snippets"))) or ("locating bug core snippets"))*.