Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"python using data snippets" » "python using java snippets", "python using sat snippets", "python missing data snippets"
"duc hoc dan snippets" » "duoc hoc dan snippets", "luc hoc dan snippets", "du hoc dan snippets"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("duc hoc dan snippets") OR ("python using data snippets"))) OR ("locating bug core snippets"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"duc hoc dan snippets\") OR (\"python using data snippets\"))) OR (\"locating bug core snippets\"))*".
• Removing quotes may allow a broader search: (((( duc hoc dan snippets ) OR ( python using data snippets ))) OR ( locating bug core snippets ))*.