Resolver problema de PageSpeed  

Hola

Si quieres que se considere cache de navegador, tendrías que agregar código a tu archivo .htaccess.

Aqui se discute el tema:
https://www.webempresa.com/foro/41-Preguntas-sobre-PrestaShop/158538-Aprovechar-el-almacenamiento-en-cach%C3%A9-del-navegador-en-gtmetrix-y-pagespeed.html

PD. Ten en cuenta que la mayoría de las veces debes tomar este punto de optimización como sugerencia y no como algo estricto que tiene que cumplir

Saludos.

Hola, si me queda constancia de solo son recomendaciones, pero la optimización en móvil me da muy baja puntuación 35/100 y quería subir esta puntuación un poco más.
Con respecto al .htacces ya lo tenía modificado. Está del siguiente modo. Aún así la puntuación no mejora.
Ya que en los enlaces que me habéis proporcionado, el tema es modificar este archivo.

# ~~start~~ Do not remove this comment, Prestashop will keep automatically the code outside this comment when .htaccess will be generated again
# .htaccess automaticaly generated by PrestaShop e-commerce open-source solution
# http://www.prestashop.com - http://www.prestashop.com/forums

SetEnv HTTP_MOD_REWRITE On

RewriteEngine on

#Domain: emsportandfashion.com
RewriteRule . - [E=REWRITEBASE:/]
RewriteRule ^api$ api/ [L]

RewriteRule ^api/(.*)$ %{ENV:REWRITEBASE}webservice/dispatcher.php?url=$1 [QSA,L]

# Images
RewriteRule ^([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$1$2$3.jpg [L]
RewriteRule ^([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$1$2$3$4.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$1$2$3$4$5.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$4/$1$2$3$4$5$6.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$4/$5/$1$2$3$4$5$6$7.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$4/$5/$6/$1$2$3$4$5$6$7$8.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$4/$5/$6/$7/$1$2$3$4$5$6$7$8$9.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(-[_a-zA-Z0-9-]*)?(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/p/$1/$2/$3/$4/$5/$6/$7/$8/$1$2$3$4$5$6$7$8$9$10.jpg [L]
RewriteRule ^c/([0-9]+)(-[.*_a-zA-Z0-9-]*)(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/c/$1$2$3.jpg [L]
RewriteRule ^c/([a-zA-Z_-]+)(-[0-9]+)?/.+.jpg$ %{ENV:REWRITEBASE}img/c/$1$2.jpg [L]
# AlphaImageLoader for IE and fancybox
RewriteRule ^images_ie/?([^/]+).(jpe?g|png|gif)$ js/jquery/plugins/fancybox/images/$1.$2 [L]

# Dispatcher
RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ %{ENV:REWRITEBASE}index.php [NC,L]

AddType application/vnd.ms-fontobject .eot
AddType font/ttf .ttf
AddType font/otf .otf
AddType font/woff2 .woff2
AddType application/x-font-woff .woff

Header set Access-Control-Allow-Origin "*"

ExpiresActive On
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 week"
ExpiresByType text/javascript "access plus 1 week"
ExpiresByType application/javascript "access plus 1 week"
ExpiresByType application/x-javascript "access plus 1 week"
ExpiresByType image/x-icon "access plus 1 year"
ExpiresByType image/svg+xml "access plus 1 year"
ExpiresByType image/vnd.microsoft.icon "access plus 1 year"
ExpiresByType application/font-woff "access plus 1 year"
ExpiresByType application/x-font-woff "access plus 1 year"
ExpiresByType font/woff2 "access plus 1 year"
ExpiresByType application/vnd.ms-fontobject "access plus 1 year"
ExpiresByType font/opentype "access plus 1 year"
ExpiresByType font/ttf "access plus 1 year"
ExpiresByType font/otf "access plus 1 year"
ExpiresByType application/x-font-ttf "access plus 1 year"
ExpiresByType application/x-font-otf "access plus 1 year"

Header unset Etag

FileETag none

AddOutputFilterByType DEFLATE text/html text/css text/javascript application/javascript application/x-javascript font/ttf application/x-font-ttf font/otf application/x-font-otf font/opentype image/svg+xml

#If rewrite mod isn't enabled
ErrorDocument 404 /index.php?controller=404

# ~~end~~ Do not remove this comment, Prestashop will keep automatically the code outside this comment when .htaccess will be generated again

Hola Mario.

Sobre los enlaces que muestra spara el tiempo de cache, estos no se pueden especificar ya que están cargando desde una URL externa, es decir, puedes especificar los tiempos de cache de tu web pero no los de los archivos que son servidos desde otras ubicaciones.

Un saludo