Talvez deva tentar algumas variações de ortografia:
perturbation python » perturbation method (Expandir a busca), perturbation methods (Expandir a busca), perturbation to (Expandir a busca)
code programming » cone programming (Expandir a busca), core programming (Expandir a busca), co programming (Expandir a busca)
c perturbation » _ perturbation (Expandir a busca), c1 perturbations (Expandir a busca), of perturbation (Expandir a busca)
coder python » codigo python (Expandir a busca), compra python (Expandir a busca)
coder coder » coder decoder (Expandir a busca), code code (Expandir a busca), decoder codec (Expandir a busca)
python code » python coding (Expandir a busca), python redes (Expandir a busca)
python c » python _ (Expandir a busca)

Você pode obter mais resultados ajustando o argumento de busca.

• Remover as aspas pode possibilitar buscas mais amplas: (( coder coder python code programming ) OR ( python c perturbation python programming ))~.