Perhaps you should try some spelling variations:
"dung truong vo snippets" » "duong truong vo snippets", "dung trong vo snippets", "dung trung vo snippets", "dung truong von snippets", "dung truong bo snippets", "dung truong va snippets"
"using java code snippets" » "using data 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 code snippets") or ("dung truong vo snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using java code snippets") OR ("dung truong vo snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( using java code snippets ) or ( dung truong vo snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") or ("dung truong vo snippets"))) or ("locating bug core snippets"))*.