Perhaps you should try some spelling variations:
"vi ung open snippets" » "vi ung code snippets", "vi dung open snippets", "vi using open snippets", "vi ung bien snippets", "va ung open snippets", "vi luong open snippets", "vi trung open snippets"
"locating bug core snippets" » "locating bug code snippets"
"using java java snippets" » "using data java 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: "((((\"vi ung open snippets\") OR (\"using java java snippets\"))) OR (\"locating bug core snippets\"))~".
• Removing quotes may allow a broader search: (((( vi ung open snippets ) OR ( using java java snippets ))) OR ( locating bug core snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("vi ung open snippets") OR ("using java java snippets"))) OR ("locating bug core snippets"))*.