Ramos, now coach of Ukrainian side Dnipro Dnipropetrovsk who hold a 1-0 lead over Spurs heading into Thursday's Europa League last-32 second leg at White Hart Lane, led the London club to the League Cup in 2008.
Tottenham have failed to add to their trophy cabinet since Ramos was sacked following a poor start to the following season, but the Spaniard said if they continue to invest in the squad the good times will soon return.
"It is a satisfaction and joy to be the last (coach) who won a title, the last trophy won by Tottenham but I think it will not be long before they win another one because each year they invest more and have a big budget, they are spending a lot of money on players," Ramos said.
"They are changing the things that are not working and I believe it will not be long until they win another title.
"But that is the reality after I left they have not won anything."
Tottenham are fifth in the Premier League and out of both domestic cups, so the Europa League remains their only realistic hope of success this season.
Dnipro hold a slender advantage after Yevhen Konoplyanka converted an 81st-minute penalty last week to inflict Tottenham's first defeat in nine matches in this season's competition.
"We got over the group stage and with the team that we have, it has been an achievement," Ramos added.
"Now we are facing a team Tottenham which is favourite to win the Europa League. We know about the difficulties that we are facing but our duty as professionals is to do everything in the best possible way to try to overcome our rivals and give some joy to our fans."
The winners of the tie will face either Greek side PAOK Salonika or last season's finalists Benfica from Portugal in the last 16.