Perhaps you should try some spelling variations:
"based populations using subsampling program" » "based populations using sampling program" (Expand search), "based population using subsampling program" (Expand search), "base populations using subsampling program" (Expand search), "aged populations using subsampling program" (Expand search), "based formulations using subsampling program" (Expand search), "based populations and subsampling program" (Expand search)
"using codigo python python programming" » "using codigo pythons python programming" (Expand search), "using codigo piton python programming" (Expand search), "using codigo pitons python programming" (Expand search), "using indigo python python programming" (Expand search), "using coding python python programming" (Expand search), "using codium python python programming" (Expand search)

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: "((\"based populations using subsampling program\") OR (\"using codigo python python programming\"))~".
• Removing quotes may allow a broader search: (( based populations using subsampling program ) OR ( using codigo python python programming ))~.
• Adding a wildcard symbol may retrieve word variants: (("based populations using subsampling program") OR ("using codigo python python programming"))*.