League's current matchmaking sounds like a joke if you think about it

• You can't enter a queue with your friend who is more than a tier lower/higher than you. Unless, that is, your other friend who is between you two in a ladder happens to be online and enters the party
• Above also means that there are people I can't enter the queue with, even if I could easily be matched with/against them
• This also means that I may happen to not be able to queue with my bronze/diamond friends and go solo, only to still have bronze/diamond players matched with me
• Entering the queue together is based on your leagues. However, matchmaking is oriented about MMR. The two don't always reflect each other, what means there are people who you won't get easily matched with, even if you could enter the queue as a party with no problem

Riot games should at least decide if they care about competitive aspect of ranked more than social, and forbid partying with players too far from you in the ladder at all, or if they care about social aspect more and allow to queue with such players with no problems.

TL;DR Fix your game Rito