Чтобы посмотреть список установленных пакетов можно использовать команду apt list.
Например, чтобы найти пакеты в названии которых встречается строка php:
# apt list --installed |grep php
libapache2-mod-php5/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php-auth-sasl/trusty,now 1.0.6-1 all [installed,automatic]
php-mail/trusty,now 1.2.0-6 all [installed]
php-mail-mime/trusty,now 1.8.8-1 all [installed]
php-net-smtp/trusty,now 1.6.1-1 all [installed,automatic]
php-net-socket/trusty,now 1.0.14-1 all [installed,automatic]
php-pear/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 all [installed,automatic]
php5/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 all [installed,automatic]
php5-cli/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php5-common/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php5-curl/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php5-gd/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php5-json/trusty,now 1.3.2-2build1 amd64 [installed]
php5-mcrypt/trusty,now 5.4.6-0ubuntu5 amd64 [installed]
php5-mysql/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
php5-readline/trusty-updates,trusty-security,now 5.5.9+dfsg-1ubuntu4.29 amd64 [installed]
