Previous and Next arrows

I do it, but in file no information about "next" "previous"

Try en-GB.ini

no

You cahnged:
JNEXT="Next"
JPREV="Prev"

right?

yes!

Ok, just download whole

<site root folder>\language\en-GB\

then find work "Prev" and "Next" in all files and everywhere you find them replace them. Then upload them back.

EDIT:

If your default language is not English then you are looking at wrong place

<site root folder>\language\xx-XX\

where xx-XX is alias for your default language.