Perhaps you should try some spelling variations:
"using java java snippets" » "using data java snippets"
"van hoang code snippets" » "van hoang de snippets", "van hoang cong snippets", "van hoang cd snippets", "van hoan code snippets", "quan hoang code snippets", "tran hoang code 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 java snippets") OR ("van hoang code snippets"))) OR ("locating bug core snippets"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"using java java snippets\") OR (\"van hoang code snippets\"))) OR (\"locating bug core snippets\"))".
• Removing quotes may allow a broader search: (((( using java java snippets ) OR ( van hoang code snippets ))) OR ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java java snippets") OR ("van hoang code snippets"))) OR ("locating bug core snippets"))*.