search-citeseer: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/search-citeseer - from package: search-citeseer

You may install the required package with command apt-get install {package}

Error in other languages:
search-citeseer: bevel nie gevind nie
search-citeseer: comandă negăsită
search-citeseer: comando não encontrado
search-citeseer: commande introuvable
search-citeseer: command not found
search-citeseer: käsku ei ole
search-citeseer: không tìm thấy lệnh
search-citeseer: komanda nerasta
search-citeseer: Kommando nicht gefunden.
search-citeseer: kommandot finns inte
search-citeseer: komut yok
search-citeseer: nie znaleziono polecenia
search-citeseer: níor aimsíodh an t-ordú
search-citeseer: no se encontró la orden
search-citeseer: no s'ha trobat l'ordre
search-citeseer: opdracht niet gevonden
search-citeseer: parancs nem található
search-citeseer: perintah tidak ditemukan
search-citeseer: príkaz nenájdený
search-citeseer: příkaz nenalezen
search-citeseer: команда не найдена
search-citeseer: командата не е открита
search-citeseer: 命令找不到
search-citeseer: コマンドが見つかりません