Perhaps you should try some spelling variations:
"coder coder berth allocation problem" » "coder coder berth location problem" (Expand search), "coder coder cost allocation problem" (Expand search), "coder decoder berth allocation problem" (Expand search), "code code berth allocation problem" (Expand search), "decoder codec berth allocation problem" (Expand search)
"_ python python python programming" » "_ pythons python python programming" (Expand search), "_ piton python python programming" (Expand search), "_ pitons 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: "((\"coder coder berth allocation problem\") OR (\"_ python python python programming\"))~".
• Removing quotes may allow a broader search: (( coder coder berth allocation problem ) OR ( _ python python python programming ))~.
• Adding a wildcard symbol may retrieve word variants: (("coder coder berth allocation problem") OR ("_ python python python programming"))*.