Perhaps you should try some spelling variations:
"using java java snippets" » "using data java snippets"
"vi trung lop snippets" » "vi truong lop snippets", "vi trung lap snippets", "vi trung long snippets", "va trung lop snippets", "viet trung lop snippets", "vien trung lop snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core 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 trung lop snippets\") OR (\"using java java snippets\"))) OR (\"locating bug code snippets\"))~".
• Removing quotes may allow a broader search: (((( vi trung lop snippets ) OR ( using java java snippets ))) OR ( locating bug code snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("vi trung lop snippets") OR ("using java java snippets"))) OR ("locating bug code snippets"))*.