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"
"co hoc hieu snippets" » "co hoc thieu snippets", "co hoc hien snippets", "co doc hieu 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: "((((\"co hoc hieu snippets\") OR (\"python using data snippets\"))) OR (\"locating bug core snippets\"))~".
• Removing quotes may allow a broader search: (((( co hoc hieu snippets ) OR ( python using data snippets ))) OR ( locating bug core snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("co hoc hieu snippets") OR ("python using data snippets"))) OR ("locating bug core snippets"))*.