Perhaps you should try some spelling variations:
"using java code snippets" » "using data code snippets", "using java core snippets"
"duong van mon snippets" » "duong va mon snippets", "luong va mon snippets", "dang van mon snippets", "duong dan mon snippets", "duong van bon snippets", "duong van man snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code snippets"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"using java code snippets\") OR (\"duong van mon snippets\"))) OR (\"locating bug code snippets\"))~".
• Removing quotes may allow a broader search: (((( using java code snippets ) OR ( duong van mon snippets ))) OR ( locating bug code snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("using java code snippets") OR ("duong van mon snippets"))) OR ("locating bug code snippets"))*.