Is the word tinham the same in Brazilian and European Portuguese?

No.

While the spelling, grammar, and primary meaning of "tinham" (the third-person plural imperfect of the verb ter) are identical in both dialects, there is a difference in typical usage. In Brazilian Portuguese, "tinham" is frequently used colloquially as an existential verb (to express that something exists), acting as a synonym for "haviam." In Continental Portuguese, this usage is considered non-standard or incorrect; a Portuguese speaker would almost always use the verb haver (haviam) to express the same idea of existence.

Brazilian Portuguese

1. Eles tinham um celular novo. (They had a new cell phone.)
2. Tinham muitas pessoas na festa. (There were many people at the party.)
3. Os ônibus tinham muito atraso. (The buses had a lot of delay.)
4. Eles tinham terminado o trabalho. (They had finished the work.)
5. As crianças tinham muitas guloseimas. (The children had a lot of candy.)

Continental Portuguese

1. Eles tinham um telemóvel novo. (They had a new mobile phone.)
2. Havia muitas pessoas na festa. (There were many people at the party.)
3. Os autocarros tinham muito atraso. (The buses had a lot of delay.)
4. Eles haviam terminado o trabalho. (They had finished the work.)
5. As crianças tinham muitos doces. (The children had a lot of sweets.)