The 28-year-old arrived at White Hart Lane in the summer for a then-club-record fee of £26m, but has only managed to find the net once from open play in 13 Premier League appearances.
"Of course it is difficult, but I certainly don't think that a change of country and a new language is any excuse whatsoever for not performing at the level that I expect of myself," The Telegraph quotes the Spaniard as saying.
"I think that I've been here for long enough now to have a good understanding with my teammates during a game which is the most important thing and let's hope that from now on you will start to see another Roberto Soldado.
"I haven't been performing how I would have expected, this fan support has always been unconditional and at least now I can show my gratitude to them with goals, which is what they want to see."
Soldado scored a hat-trick in Thursday's Europa League victory over Anzhi Makhachkala.