Combining voltages sources to increase current
You are finding conflicting answers on Google because both "yes" and "no" are correct depending on the context.

Why no is correct:
If you have a fixed resistor that represents your load, the current through the resistor is governed by Ohm's Law: \$I=\frac{V}{R}\$. Current through the resistor is the same no matter how many power supplies you have in parallel. This is, of course, assuming the power supplies are all set to the same voltage. The only way to increase current through the load is to decrease the load's resistance and/or increase the voltage if the power supplies.

Why yes is correct:
If you have a circuit that is trying to draw more current than the power supply is capable of supplying, then adding more power supplies will increase the current. Think of attaching a small battery to a DC motor. Maybe just one battery isn't enough to fully power the motor. But add a few more batteries in parallel and you can get the motor to rotate at full power. However, after a point, adding more batteries won't make the motor turn faster for the reason stayed in the paragraph above.

The circuit you drew is correct if the resistor is 2.67\$\Omega\$. Each voltage supply will contribute 1/3rd of the .75A. If you added a 4th supply, the current through the resistor wouldn't change (V and R haven't changed), but each supply would now contribute 1/4th of the .75A.