Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets"
"van tinh son snippets" » "van thinh son snippets", "van minh son snippets", "ban tinh son snippets", "van tinh toan snippets", "van dinh so snippets", "van tinh hoc 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 tinh son 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 tinh son snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( van tinh son snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("van tinh son snippets"))) or ("locating bug core snippets"))*.