Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets"
"locating bug core snippets" » "locating bug code snippets"
"van dan hoc snippets" » "van ban hoc snippets", "ban dan hoc snippets", "van dao hoc snippets", "van van hoc snippets", "van dan toc snippets", "van dai hoc snippets"

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

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